Preheat oven to 350°F. Meanwhile grate 8 ounces of mozzarella cheese on the large holes of a box grater. (Note: It's best to grate an 8-ounce chunk of cheese instead of using pregrated -- pregrated is coated with cornstarch to keep it from clumping, and that affects even melting.)
Make a chiffonade of fresh basil using about 6 large leaves.
Cheese and Repeat
Repeat process with second portion of dough, remaining sauce, another dusting of Parm, and the remaining mozzarella. Add some more basil.