In a mixing bowl, combine the eggs, milk, cheese, bacon and spinach.
Spray a muffin tin with non-stick baking spray.
Add the egg mixture to the muffin tins.
Bake for 18 - 20 minutes or until the eggs are fully cooked.
Notes
Refrigeration: Any leftovers can be stored in an airtight container in the refrigerator for up to 3 days. I like to use glass storage containers
Freezer: Allow the egg muffins to cool completely. Then place them on a baking sheet lined with parchment paper. Add the baking sheet to the freezer and allow the egg muffins to flash freeze. Once, frozen, place in freezer-safe storage bags or containers.
Reheating Tips: To reheat egg muffins in the microwave for a minute or two until warmed through. To defrost egg muffins, you'll need a few more minutes until the eggs have defrosted.