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A veggie-packed Sausage Macaroni Casserole where the pasta bakes right in the oven and gets finished with melty mozzarella.

Chicken sausage, bell peppers, onions and mushrooms simmered in a marinara sauce then baked in the casserole with whole wheat macaroni topped with mozzarella.

Macaroni and Sausage Casserole

I love a baked pasta dish that doesn’t require having to cook the pasta. Why dirty an extra pot? Instead, you pour the sauce over the macaroni, and it cooks in the sauce, right in the oven. Although it takes about 55 minutes to bake, it’s hands-off time, so you can relax while dinner’s in the oven.

Why This Recipe Works

This macaroni and sausage casserole was inspired by the Easy Macaroni Casserole, which has ground turkey and veggies. Every time I made it, I thought, “I bet this would be great with sausage and peppers.” I finally tested it, and I was right! Here are more reasons I think you’ll love it.

One-pan cooking: The pasta cooks in the sauce, so there’s no need to boil it separately. Saves time, effort, and dirty dishes!
Family-friendly comfort food: If your kids love macaroni and cheese and spaghetti with red sauce, this sausage pasta bake will be a definite win.
Convenient for busy days: Assemble it a day in advance so it’s ready to pop in the oven right before dinner.

Ingredients You’ll Need

Here’s more info on all the ingredients for this easy sausage macaroni casserole recipe. See the recipe card below for the exact measurements.

Chicken Sausage: Remove the casings from raw sausage.
Olive Oil to grease the pan
Aromatics: Chopped onion and garlic
Vegetables: Red and yellow bell peppers, mushrooms (white button or baby bella)
Canned Petite Diced Tomatoes: Drain them first. Regular diced tomatoes work, too.
Marinara: Use homemade marinara sauce or your favorite jarred sauce to save time.
Water helps cook the pasta in the oven because we’re not pre-cooking it in boiling water.
Seasoning: Kosher salt, Italian seasoning
Mozzarella Cheese: Shred a ball of fresh mozzarella.
Elbow Pasta: DeLallo’s whole wheat pasta is the only whole wheat pasta I like, and you can’t even tell it’s whole wheat in this dish. If you can’t eat gluten, use gluten-free macaroni.

How to Make Sausage Macaroni Casserole

Everything cooks in one large skillet, then it’s combined with the uncooked pasta in a baking dish and baked until warm and melty. See the recipe card at the bottom for printable directions.

Brown the raw sausage before adding it to the casserole. Break it into smaller pieces as it cooks, then transfer it to a bowl.
Cook the onions, garlic, and peppers in a nonstick skillet until soft.
Add the remaining ingredients–sausage, mushrooms, tomatoes, marinara, water, and seasoning–to the pan.
Simmer: Bring the skillet to a boil, then reduce the heat and let it simmer for 10 minutes. Taste the sauce to ensure it is good. Now’s the time to add more salt or seasoning if needed.
Assemble the casserole: Spread the sausage mixture over the bottom of a 9-by-13-inch pan. Add the uncooked pasta, then the remaining sauce, making sure the sauce completely covers the dry pasta. Sprinkle with mozzarella.
Bake the macaroni casserole: Cover the dish with foil and bake for 50 to 55 minutes. Let it rest for 15 minutes before serving.

Variations

Sausage: Substitute ground chicken, turkey, or beef, or use turkey sausage. Italian sausage would also be good.
Make it vegetarian and leave out the sausage.
Hate mushrooms? Omit them and add more bell peppers. You could also use chopped carrots, celery, yellow squash, or zucchini. Add the carrots and celery with the bell peppers, and the squash and zucchini when you would add the mushrooms.
Liquid options: Swap water with chicken broth for more flavor or chicken bone broth for extra protein.
Dried Herbs: If you don’t have Italian seasoning, substitute dried thyme, oregano, or parsley, or a combination of all three.
Add some heat: Sprinkle in crushed red pepper flakes or use spicy sausage or red sauce.
Dairy-free pasta: Skip the cheese or use a plant-based alternative.
Pasta types: You can use any short pasta shape, such as fusilli, orecchiette, or farfalle. If you use regular pasta, it will cook faster than whole wheat pasta, so check it around 30 to 40 minutes.
Can I use cooked pasta? If you prefer to boil the pasta separately, omit the water and bake the casserole for 25 minutes.

Meal Prep and Storage

Can I make this baked macaroni casserole in advance? If you want to assemble it early, prepare it through step 7. Cover the casserole with foil and refrigerate for up to 24 hours. While the oven preheats, let it sit at room temperature, then bake as instructed.
Refrigerate leftover pasta for up to 4 days.
Not feeding many people? You can easily halve this recipe to fit a 9-by-9- inch baking dish and serve four people.
Can you freeze the leftovers? Yes! Let the casserole cool before freezing. For individual servings for future lunches, store the pasta in 1.5- cup glass containers. Alternatively, freeze half in a larger dish for a future family dinner. Leftovers will keep for up to 3 months in the freezer.
How to thaw: Place the dish in the refrigerator the day before eating. Then microwave or bake at 350°F until warm.

More Easy Pasta Recipes You’ll Love

For more dinner ideas using pasta, check out these five delicious baked pasta recipes to inspire your next meal!

Skinnytaste High Protein cookbook protein

Disclosure: This post is sponsored by DeLallo. I only share products I use in my own kitchen. I created this recipe and received compensation to do so.