Spray your mini muffin tin with cooking spray or butter
In a medium mixing bowl, whisk together the eggs and milk, then add in the spinach, cheese, garlic powder and salt and stir to combine.
Add 1 TBSP of the mixture to each of the muffin cups.
Bake for 13 minutes and then remove the eggs from the pan immediately to cool. They will deflate as they cool.
Arrange on a baking sheet and freeze for about 2 hours and then transfer to a freezer bag and store in the freezer for up to 3 weeks. When it’s time to eat, just pop them in the microwave for about 30 seconds and they’re ready to go.