Preheat your oven to 375°F (190°C) and grease or line a 12-cup muffin tin.
Roll out pie crusts and cut 3.5-inch circles. Press them gently into muffin cups and pop the tin in the freezer while making filling.
Whisk together eggs, milk, cream, salt, and pepper in a large bowl until fluffy.
Stir in spinach, onion, ham, and cheese.
Fill each cup almost to the top with egg mixture.
Bake for 25-30 minutes until centers are set and edges are golden brown.