Place broccoli, peppers, and feta cheese into muffin cups that have been coated with cooking spray.
In a measuring cup, beat eggs until smooth. Season with salt and pepper.
Pour the beaten eggs into each muffin cup until the egg mixture reaches three-quarters of the way to the top
Bake for 20 to 25 minutes, until the egg muffin cups are set. Let cool for a few minutes, and then remove them from the pan and enjoy immediately, or let cool completely and refrigerate or freeze for later.