Spray an 9 x 13-inch baking dish with cooking spray.
In a large bowl combine all the ingredients and mix with a spoon, it will be fluffy and you will think you did something wrong, don't worry, you are doing fine.
Pour into baking dish and bake 55-60 minutes, or until the edges are golden.
Let it cool a few minutes before cutting.
Video
Notes
Variations:
Add some Parmesan cheese for more flavor
Add fresh herbs like chives
Let me know in the comments what variations you like to make!