Preheat oven to 450 degrees. Spray muffin tin with non-stick cooking spray.
Microwave frozen vegetables for 3-4 minutes, or until thawed. Squeeze dry.
In a large bowl, beat eggs until foamy. Add veggies, 1/4 cup cheese, salt and pepper. Stir until well combined. Divide egg mixture into 10 muffin molds. (Fill about 3/4 full). Top with remaining (1/4 cup) cheese.
Bake for 20-25 minutes, or until eggs are set and slightly browned on the top. Remove from the oven, and let cool until able to handle. Remove by sliding a knife between the egg and the muffin tin to loosen frittata. Enjoy warm!