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Caramelized Onion, Red Pepper and Zucchini Frittata

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Caramelized onions, sautéed red bell peppers and zucchini mixed with Parmesan creates a easy frittata perfect for breakfast, lunch or dinner!

Caramelized onions and sautéed red bell peppers and zucchini mixed with eggs and Parmesan create a winning egg frittata breakfast dish.

Caramelized Onion, Pepper, Zucchini Frittata

Frittatas are a very versatile egg dish. Not only are they great for breakfast, but they also can be eaten for lunch or dinner if paired with a salad. Frittatas are a great way to clean out the refrigerator because you can fill them with your favorite ingredients. Anything goes! For some more vegetable frittata recipes, check out this Swiss Chard Frittata and this Mushroom Shallot Frittata. And if you want to make a quiche, try this Crustless Broccoli Cheddar Quiche or these Petite Crustless Quiches.

Caramelized Onion Red Pepper and Zucchini in a skillet.

Bell peppers and zucchini are in season now, and using them in your frittata is a great way to utilize them.

To make this oven-baked frittata, start by sautéing the vegetables on the stove and then pour in the whisked eggs. Once the eggs begin to set after a couple of minutes, put the skillet in the oven at 400 degrees and bake for 10-15 minutes.

If you don’t have a cast-iron or other oven-proof skillet, you can cover the frittata and cook it on low heat. When it’s almost done, flip the frittata over onto a plate. Then slide it back into the pan, so you can finish browning the frittata on the other side. You can also bake the egg mixture in a glass baking dish. After you cook the vegetables, mix them with the eggs, and pour into a 9-inch deep pie or square baking dish. Bake for about 25 minutes at 400 degrees.

What’s the difference between a quiche, omelet, and frittata?

Quiche is an egg custard dish that combines eggs with cream or milk. The quiche fillings are mixed in with the raw eggs and then baked in the oven. Quiche typically has a crust, but you can also make it without

When cooking an omelet on the stove, you put the filling on top of the cooked eggs and fold half of the eggs over the omelet toppings. Some delicious omelet recipes to try are this Tomato Mozzarella Egg White Omelet and this Broccoli and Cheese Omelet.

For a frittata, you cook your vegetables first and then mix the filling into the raw eggs. You also start cooking the eggs on the stove and finish baking them in the oven.

Another difference is that omelets are usually a single serving while frittatas and quiches are multiple servings. 

Can you freeze leftover frittata?

Yes, you can freeze leftover frittata. Cut the frittata in individual portions and wrap tightly in plastic wrap or put in a zip-lock bag. Thaw overnight and then microwave for 30-60 seconds before eating. You can freeze frittatas for up to three months. 


  • Switch out any of the vegetables with whatever you have on hand. Asparagus, broccoli, and bell pepper would all be delicious options.
  • Save time cutting the zucchini by using your food processor for a quick chop.
  • Sub the parmesan for goat cheese, pecorino romano, or feta or skip the cheese altogether. 
  • Add Italian sausage or chicken for some extra protein. 
  • To make the frittata lighter, use half eggs and half egg whites. For every egg that you substitute, use two egg whites.
  • Make frittata muffins by pouring the egg mixture into a muffin tin and baking at 350 degrees for 25 minutes.
  • If you need to feed a crowd, you can double the frittata and bake in a 9” x” 13” glass baking dish.

Brown eggs on a plate and vegetables cut up.Eggs poured into a skilletCaramelized Onion Red Pepper and Zucchini FrittataCaramelized onions and sautéed red bell peppers and zucchini mixed with eggs and Parmesan create a winning egg frittata breakfast dish.

More Frittata Recipes Will Love:

Caramelized Onion, Red Pepper and Zucchini Frittata

4.83 from 23 votes
Caramelized onions, sauteed red bell peppers and zucchini combined create a winning egg frittata breakfast dish.
Course: Breakfast, Brunch
Cuisine: Italian
Caramelized onions and sautéed red bell peppers and zucchini mixed with eggs and Parmesan create a winning egg frittata breakfast dish.
Prep: 5 minutes
Cook: 35 minutes
Total: 40 minutes
Yield: 4 servings
Serving Size: 1 /4th


  • 1 white onion, thinly sliced
  • 1 medium red bell pepper, diced
  • 1 1/2 cups zucchini, diced into matchsticks
  • 6 large eggs
  • 1/4 cup Parmesan cheese, grated
  • 2 tsp olive oil
  • salt and fresh pepper, to taste


  • Preheat oven to 400F. Over medium-low heat, heat oil in a 10-inch skillet. Stir in onion and cook until slightly brown, about 10 minutes. Add peppers and cook 5 more minutes, then add zucchini. Season with salt and pepper and cook 3 more minutes stirring occasionally.
    zucchini cut into matchsticks
  • In a medium bowl whisk eggs, Parmesan, salt and pepper.
  • Add eggs to the skillet making sure eggs cover all the vegetables. When the edges begin to set (about 2 minutes) move skillet to oven.
    Eggs poured into a skillet
  • Cook about 10-15 minutes, or until frittata is completely cooked.
    Caramelized onions and sautéed red bell peppers and zucchini mixed with eggs and Parmesan create a winning egg frittata breakfast dish.
  • Serve warm, cut into 4 pieces.

Last Step:

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Serving: 1 /4th, Calories: 186 kcal, Carbohydrates: 8 g, Protein: 13 g, Fat: 11.5 g, Saturated Fat: 4 g, Cholesterol: 284 mg, Sodium: 226.5 mg, Fiber: 2 g, Sugar: 4 g


Caramelized onions, sauteed red bell peppers and zucchini combined create a winning egg frittata breakfast dish.
Caramelized onions, sauteed red bell peppers and zucchini combined create a winning egg frittata breakfast dish.
Sautee zucchini, peppers and onions to put in the frittata.
Pour egg mixture over sauteed veggies.

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136 comments on “Caramelized Onion, Red Pepper and Zucchini Frittata”

  1. I have made this dish many times and it always comes out perfect. I like to add in different vegetables and meat. I added a jalapeno pepper, a little pepper jack cheese and two slices of crispy bacon this time. I’m sure it will be delicious! Thank you Gina, I love all your recipes.

  2. This was fabulous. I did add a third more of all the veggies and some asparagus but otherwise it was

  3. This is a great dish. I was very low on parmesan so I subbed cotija. For my WW people, there is no difference in points there. I also make my own salsa and top this dish with that. Very nice. I make a double batch and bake it so I can eat it for lunch and dinner at school. I’m a teacher.

  4. It looks like you’ve had this recipe posted for quite a few years, but I just found it and am glad I did! Great way to use up some veggies in partial disguise. Very tasty dish! Thanks for the great recipe!

  5. Avatar photo
    Consuelo Weinstein

    I made it with egg whites because my husband is on a diet. I used fresh Parmesan cheese. It was delicious! Thank you for the recipe. 

  6. What a delicious recipe and so easy to make.  I served it our Mother’s Day brunch and everyone liked the texture and taste.

  7. This was delicious; in fact, I’ve tried a few of your egg dishes and they are all excellent. Thank you 🙂

  8. Avatar photo
    Kearsley Troll

    I had leftover zucchini, peppers, and onions in the fridge and didn’t want them to go bad…and WOW! This was so simple and delicious. I didn’t have parmesan cheese so I replaced that with feta and once it was all done topped it with some fresh cilantro. Amazing recipe!

  9. Avatar photo
    Michelle Meek

    Replaced parmesan with feta and it turned out absolutely delicious. This recipe is a keeper!

  10. Looks amazing and I can’t wait to try it. Has anyone tried this using phyllo dough instead of a regular pie crust?

  11. YUMMY! A great way to use leftover veggies. My additions were some of the chicken sausage, garlic powder and feta on top. The caramelized onions really add the good flavor.

  12. This was one of the most flavorful breakfast dishes I have made. I was sad when I had eaten it all. Will definitely be making this again!

  13. Made this for lunch, it was delicious and used up some fresh summer vegetables I still had before my weekly shop. Also, it’s very quick and easy. Thank you!

  14. Avatar photo
    Lyn-Anne Williams

    This frittata is excellent! I have made a bunch of your recipes, and they never disappoint. I just thought it was time for me to post a review. Ha Ha.

  15. This was so easy and so delicious! And all the protein from the eggs helped me stay full for a while. I usually don’t even like zucchini that much but the matchstick slices were such a great touch to make the flavor blend with the other ingredients.

  16. Although all of the ingredients sounded good, this dish was a disappointment. It had no flavor at all. Maybe it would have been tastier replacing the parmesan with a spicier shredded cheese. 

    1. I would add some cayenne or chili powder to spice it up, or a few dashes of tabasco. You could also add some Italian seasonings to the eggs. Or pepper jack cheese?

    2. I would add a different cheese which is what I did. I also know that a flavored salt and pepper can add a zip. I always like salsa on my egg dishes. Keep trying!! Be creative. These are her ideas and we have to use what she has created and think how we might want to change it. Hang in there!!

  17. This was the frittata I’ve ever made, and it was so simple and delicious it makes me sad that I hadn’t done it before. This is definitely going into my “favorites” board.

  18. One of the things I really love about recipes like this is that they can be adapted to use a variety of ingredients. I am thinking of turning this into a crustless quiche.

  19. I made this last night for breakfasts for the week. It smelled delicious, tasted even better and was easy to make! I passed this recipe on to two colleagues the day after making it! The portions are huge and only 4 pt+!!! Thank you for including the nutritional information. it makes it easy to calculate the points. I will make this again and look at other recipes on your site.

  20. I love this recipe….. I’ve made it a bunch of times!!! I’d like to make it for my family as part of our Christmas breakfast so i would like to do it in a 9×13…..  what do you suggest? 

  21. Can you freeze this and reheat in microwave? I’m looking for an easy breakfast because I leave early in the morning. 

    1. I make this every Sunday and my husband eats it throughout the work week. This has been going been going on for years!! Delish.

  22. This was really good!! My daughters both loved it and they are ages 3 and 1. Thank you! Side note, I used 6 whole eggs and baked it in a dish and it turned out great!

  23. Avatar photo
    Barbara korpacz

    Hi Gina
    Can you tell me how the smart points will change if I use low fat cheddar jack cheese. Also, can I add more veggies?

    Thank you.

  24. This made a very nice dish for brunch today!  Didn’t have enough zucchini, so we increased the bell pepper, and added a bit of sliced mushrooms.
    Excellent meal — we each said “5-star”

  25. I just made the fritata this morning. It was very delicious! I was wondering if I could freeze the leftovers to have at a later date. How can I do that?

  26. Made this last week. Liked it so much, I made it again this week. I froze individual slices to have for breakfast this week. Yum!!

  27. Guess what's in my oven right now? You guessed it! I only recently found out I'm NOT allergic to eggs, as I believed my whole life. So I'm starting to experiment. I didn't have any zucchini, so I grated in some broccoli instead. I also threw in a little finely diced fennel bulb, tomato, and added a little basil to the top before throwing it into the oven. I can't wait to try it.

  28. I roasted the red pepper instead of using raw red peppers and it was delicious. It added a great sweetness to it. Love this recipe!

  29. Avatar photo
    Brittany Reader

    This was my first time making a frittata, it was so easy and delicious! I baked it in the oven in a glass pan, and I also added some spinach for extra veggies. So good! Can't wait to try some of the other ones. Thank you for all of your wonderful recipes, even my super picky husband has loved every single one that I've made! 🙂

  30. I've made this many times and love it! I couldn't really taste the parmesan so lately I've been subbing goat cheese for it and I think it's even better!

  31. I've made this many times and love it! I couldn't really taste the parmesan so lately I've been subbing goat cheese for it and I think it's even better!

  32. Is it possible to use all egg whites for this recipe? If so instead of a total of 8 egg whites would I need more? Or could I keep it the same?

  33. Avatar photo

    Great recipe! I "used what I had" as far as the veggies and cheese. I only had (gasp) frozen veggies! (onions, peppers, broccoli, carrots) and less than 1/4 cup of parm, but it was still delicious! 1/4 of this recipe is a generous serving IMO.

  34. Made this dish for brunch and it was great. Easy to follow instructions and it turned out picture perfect. I did add turkey bacon bits to half of it but it really tasted better without them.

  35. Avatar photo
    Lisa Shapiro

    Gina, Can you think of another veggie that wouldn't add too much moisture besides red or green bell peppers? (I'm allergic). Thanks.

  36. We made this dish this morning and it was great! Nice and fluffy and had a good flavor for a low calorie dish! I have used several of your recipies and they have all been great! Thanks for the wonderful ideas and the pictures help me imagine what the dishes will look and taste like. Thank you!

  37. Hi Gina!!
    First I have to say I'm a huge fan of your blog. My mom and I have been on Weight Watchers for a little over a year now and I've lost about 70lbs and she's lost about 40lb. We rave about your blog in almost every meeting we go to. Your recipes are a major factor in our success because they keep us excited about the things we eat! I don't think there has been anything we've made from your site that we haven't loved!
    I just had to comment on this frittata becuase I made it recently as per your instructions and thought it was delicious! The second time I decided to try to make it as mini muffin sized frittatas. I diced all of the veggies so that they would fit nicely in the muffin tin. I still cooked them based on your instructions, except after the zucchini was added in and cooked, I removed the veggies from the heat and allowed them to cool for a few minutes, then I added that mixture into the egg mixture. I poured a 1/4c into each section of the muffin pan (sprayed with some olive oil spray) and then I cooked them at 350 for 25 minutes. It perfectly made a dozen mini frittatas. We each got 3 "muffins" and served with some fruit on the side it was the perfect breakfast!

    Thanks again for all of your great recipes!

  38. I made this tonight for dinner and the only thing I would comment on is that it was a little bland. I only seasoned with pepper because my husband and I don't cook with salt. I'm sure it would be better with salt, but next time I make it I'm going to season the veggies before I add the egg and cheese. I usually use Italian Seasonings, Garlic Powder, Oregano, and Chili Powder. Overall, it was a great, healthy meal that I will definitely make again!

  39. Yummy! I just started WW and this is the first time in 3 days that I've been full! It came out perfect for me, and I followed the directions exactly EXCEPT I just used my food processor for everything, so my zucchini was just in thin discs, not pretty match sticks. I was in a hurry, and it tasted great even without the match sticks!

  40. Great recipe! I have made this SO many times, a million different ways, and it has completely revolutionized my cooking repertoire! No longer is soup the only thing I can make at the end of a week with leftover veggies… now we have an amazing frittata, healthy and so tasty (like so many of your recipes! I don't know how you do it, but I'm glad you do!), it's the perfect dish.

  41. delicious!! I made this using a cup of egg beaters and 12 TBSP egg whites from a carton. i also sprinkled in some garlic powder and Italian seasoning in addition to the salt and pepper. Since I don't own an own proof frying pan i simply sauteed the veggies, added them to the egg mixture, and then added the whole thing into an 8X8 PAM sprayed pan. Baked for about 40 minutes. Will be making this again and again 😀

  42. I made this today as a dinner dish and went exactly by your recipe…turned out really nicely…we loved it! Thank you for sharing! 🙂

  43. Once in a while I will make 'breakfast 4 dinner' for my family. I'm on Weight Watchers and as my children ate chocolate chip pancakes I fully enjoyed this frittata! I substituted the parmesan for goat cheese and used my amazing food processor attachments to matchstick the zucchini…it cut the time down quite a bit. Thank you for having this amazing website…I'd love to know if and when you will have a book!!!!

  44. I made this tonight for dinner for a gf…and it turned out amazing! Served it with a light Greek salad and will def make it again!!

  45. SO GOOD! We made it tonight and it came out of the pan (All Clad) perfectly. It was so flavorful! Thanks for another great recipe!

  46. I made this tonight for dinner and it was delicious! Not too eggy. I love that it was packed full of veggies. I added a little garlic powder to the veggies while they were sauteeing for some added flavor. Can't wait to make this again!

  47. Hey Gina! I love all of your recipes, I was wondering if I could make this say on Sunday and have it for breakfast for a few days? Does anyone know if keeps well, how long and if it would be freezable? Thanks in advance!

  48. Yum! Swapped out the zucchini for choppedc up lite turkey sausage. I had no idea how easy it was to maje a frittata!

  49. Just made this tonight. It was delicious!! I don't have a skillet to oven baking dish so , once the veggies were done, I poured them into the bowl woth the whisked egg and parm cheese, mixed gently and poured it into a pie plate to bake. Sooo good.

  50. Just made this for brunch today – used 6 egg beaters & 2 real eggs and sprinkled some goat cheese on the top for the last 5 minutes in the oven. Perfection! Thank you for introducing me to the wonders of the frittata!

  51. I made this last night and instead of red peppers because I'm allergic, I used mushrooms. Sadly, I think I may have had the heat on too high on the stovetop befor I put it in the oven, because it was very brown on the bottom. Any suggestions? Thanks, Gina! Keep up the good work!

  52. This was just okay on my first attempt. It was kind of bland due to the amount of egg whites, BUT a section that got messed up in the pan as I turned it out was more eggie and yummy. I am not sure what happened because I did whisk the eggs well. I WILL try it again with one less white and one more yolk. I feel like I can get this to work for me.

  53. Loved the recipe! Cheated a bit by adding tiny dollops of herbed goat cheese on the top before baking. Thanks for a great one!

  54. We made this tonight and it was so delicious and so easy to make! Going to put this one in my recipe book. 🙂

  55. I made this for dinner last night to go along with a bowl of homemade tomato soup and fresh salad. Really satisfying meal for only 7 points total (soup, salad, and fritatta)! Even better, DH really liked the fritatta and there was one square left for my breakfast this morning! This recipe is a definite keeper and I'll be making it again soon. Made exactly as directed this time, but will probably add mushrooms on the next go around. THANKS! 🙂

  56. Avatar photo
    Ashli Phillips

    I have some yummy recipes that are also healthy on my blog! Check it out!

  57. I made this tonight and it was fantastic! I added mushrooms because I had some in the fridge that I wanted to use up. I have many many of your recipes in the past 4 weeks. Your recipes make me excited to cook! Thank you!

  58. I make all my frittata similar to you by using 1/3 f the egg yolks. There's enough fat from the remaining yolks for taste and texture, but you are cutting the amount of fat and cholesterol from the eggs in half. I even make regular scrambled and "fried" eggs that way (generally 1 whole egg and 2 egg whites per serving).

  59. Avatar photo
    Jen @ Peanut Butter and Peppers

    Beautiful dish! I love making Fritata's, espeically individual ones. Love this recipe!!

  60. Doing low carb, this looks great….I always check out your recipes because you always have something I can make and that makes me happy!

  61. Avatar photo
    Gina @ Skinnytaste

    For all of you asking ablout how to cut the zucchini, I added photos to help!

    Zina, how nice!

    Anonymous, if your not a huge fan you can certainly use less.

  62. AWESOME! I used a whole onion – overpowering. Next time I will cut back and dice it instead, or use another veggie. This is really great and the calories are fantastic for the volume you get!

  63. Avatar photo
    Zina :: Let's Lasso the Moon

    I listened to a sermon this weekend about how one could find God while cutting a beautiful red onion. 🙂 It was "interesting," but thought provoking nonetheless. So your title in my inbox this morning made me smile.

  64. LOVE the serving size!! Took me a few seconds, but I got it…can't wait to try 20 minutes of it later today 😉

  65. You are using a stainless pan… how did you get it out of the pan??? Lots of spray?? Looks delicious, thanks!

  66. YAY another Frittata! I love your frittatas so I can wait to try this one since I love zucchini & red peppers. Yummy! Thanks Gina 🙂

  67. My husband has just discovered, he likes frittata so this is just right for us. Beautiful presentation.

  68. I used a cheese grater on the largest hole to "matchstick" the zucchini. It was a tad smaller than matchstick but it saved time chopping and turned out yummy. Everyone even my 4 year old picky eater loved it. Thanks for a great, easy, healthy recipe. 🙂

  69. If you don't have a skillet that is oven-safe, is there an alternative way to finish cooking the frittata? Thanks!

    1. Avatar photo
      Gina @ Skinnytaste

      Sure, cover it and cook it on low heat, then flip it over onto a plate and finish browning on the other side.

    2. I don't have an oven proof skillet, either so I cooked the veggies in a skillet then poured the eggs in a round glass pie pan and added the veggies to have to bake just a moment or two longer but it worked great and was so delicious !

  70. I think I need a tutorial in how to cut zucchini! How did you get your so thin and even? Are you using a special tool or do I really need to spruce up my knife skills? (zucchini sticks are baking in the oven…this one is going on the menu for this weekend!)

  71. Avatar photo
    Tara @

    Gi- I love frittata's & am def making this. I love that they are even better as leftover's which I usually hate! Remind me to tell you about the salad I had yesterday…you have to make it….still thinking about it today! xoxo

  72. I have two questions 🙂 what kind of skillet is best for this? I only have nonstick ones- would these work?

    Also, what is the best way to cut the zucchini into matchsticks? Yours look so perfect!

    I've never had a frittata, but I have all the ingredients for this one and it looks yummy!

    1. Avatar photo
      Gina @ Skinnytaste

      An oven safe skillet that can withstand the heat.

      If you don't own one, you could cover it on low and let it cook in the pan, and flip it to brown the other side once it is set. The oven is easier IMO.

    2. I cut my zucchini into long strips just like in the above photo and then cut into small matchsticks…it turns out really nice that way! 🙂

  73. My fiance and I have been debating about "red peppers." When we see this ingredient should we assume red BELL pepper? Or is there another kind of pepper that is actually called a red pepper? Thanks in advance for clearing this up. PS: We made this recipe a couple of weeks ago and loved it! We used bell pepper (: -Alexz

  74. This looks so delicious and also you make it look very easy. Will definately be trying this.

    I love all of your recipes and I have been reading your blog for a little while now. Keep up the great work!

    Take care,