Preheat oven to 400°F.
Coat twenty-four 1 3/4-inch muffin cups with cooking spray.
In a medium bowl, whisk together 3 eggs, the ham, 1/3 cup of the cheese, cream, spinach, salt, and black pepper until well combined.
On a lightly floured surface, roll pastry to a 15x10-inch rectangle. Cut pastry into twenty-four 2 1/2-inch squares. Press squares into greased muffin cups. Into each of the cups, spoon about 1 tablespoon of the egg mixture.
Sprinkle cups with remaining cheese. Bake 13 to 15 minutes or until puff pastry is golden brown and filling is set.
Cool cups in pans 5 minutes. Carefully remove and transfer to a serving platter to serve.