Preheat oven to 350 degrees. Spray muffin pan generously with non-stick cooking spray. Crack eggs into a medium-sized bowl, add salt and pepper, and whisk. Dice ham and finely chop chives. Fill each muffin tin 2/3 of the way full with the eggs. On top of the beaten eggs, add the ham, cheese, and chives. Bake in the oven for 15-20 minutes or until the eggs have puffed up and set.
**This recipe can be made with any toppings you want. It is great to make as a “frittata bar” where guests can add their own toppings when they get to your house and then you can pop it into the oven. It is also a fun idea for kids to make together the morning after a sleepover!**