Lightly spray the muffin pan (or silicon muffin cups) with some olive oil. Chop up all the veggies and divide them up among the cups (about halfway full)
Whisk together the eggs, salt, pepper, and chili powder until well combined
Fill each muffin cup a little over three-quarters of the way to the top with the egg mixture
Sprinkle cheese (if using any) evenly over the tops of the cups. Stir well with a fork
Bake for 20 minutes. Let it cool. Then peel off the muffin cups.
Serve with avocado, hot sauce on top, and/or with potato hash. Enjoy!