Preheat oven to 375°F In a large mixing bowl, scramble your eggs, milk, salt and pepper. Add Spinach cheese and hash browns; stir until evenly incorporated
Pour egg mixture into lightly greased nonstick muffin tin. Place in center rack of oven and bake for about 25-30 minutes until center of egg is no longer runny. Use a spatula to remove frittatta muffins from tin and serve.
Store the remainder in an air tight contain and reheat in the oven for 10 minutes (or in the microwave for about 45 seconds) enjoy!
Notes
Poking the center with a toothpick to check to see if its runny is a good way to check for doneness!