These can be made up to 5 days in advance. Store in an airtight container with wax paper in between layers. They will brighten up any cocktail party or appetizer table! You will need 3 in. and 2 in. star cookie cutters.
Place oven rack in middle position. Heat to 400°F Coat baking sheet(s) with non-stick cooking spray. Have ready 3 inch and 2 inch star cookie cutters.
Working with 1 tortilla at a time, brush one side with butter; sprinkle with cheese. Gently press to adhere. Turn tortilla over, brush with egg white and sprinkle with 2 to 2 1/2 teaspoons of a topping.
Cut 3 inch stars from edge of tortilla, 2 inch stars from center (bake scraps for snacks). Place cheese side down on baking sheet(s).
Bake on middle oven rack 6 to 8 minutes until light golden and crisp.