1.Preheat the oven to 425F. Lightly oil a 12 cup muffin tin, or coat it with nonstick spray.
2.Working one at a time, lay a tortilla on a flat surface. Using an empty 14 half ounce can, cut out 3 rounds from the tortilla, pressing firmly and using a rocking motion to cut all the way through the tortilla. Repeat with the remaining tortillas.
3.Press a tortilla round into each of the 12 prepared muffin cups, pressing down carefully to create a well in the center of each cup. Scoop 1 tablespoon pizza sauce into each muffin tin. Sprinkle with the mozzarella and Parmesan, dividing it evenly, and top each pizza with 3 to 5 slices of mini pepperoni.
4. Bake for 10 to 12 minutes, or until both cheeses have melted.
5. Serve immediately, garnished with basil, if desired.