Preheat the oven to 350 degrees F (175 degrees C).
Cut each puff pastry sheet into 9 squares. Roll each square to fit individual 3-inch pie pans. Set puff pastry inside pie pans and place on a rimmed baking sheet. Pour a small amount of ceramic beads into each pie pan.
Bake in the preheated oven for 5 minutes.
Meanwhile, whip together eggs, spinach, milk, ricotta cheese, Parmesan cheese, mozzarella cheese, fontina cheese, salt, and pepper.
Remove pie pans from the oven and remove the ceramic beads. Ladle egg mixture into each pie tin. Bake until light golden brown, about 30 minutes.