Preheat oven to 350 F, and generously spray a 12-cup muffin tin pan with cooking spray.
In a medium bowl, whisk together the eggs, cream, salt, and pepper.
Sprinkle the veggies evenly into each of the muffin cups. Then pour an even amount of the eggs into each (you'll fill your muffin cups about 3/4 of the way). Sprinkle the tops of each with cheese.
Bake in the preheated oven for 20-25 minutes, you'll know your frittata muffins are done once they're set and lightly golden on top. Enjoy!