Preheat oven to 400°F. Lightly spray a casserole dish or 9-inch pie pan with cooking spray. Set aside.
Flatten each biscuit with the palm of your hand (or rolling pin). Sprinkle mozzarella cheese and pepperoni onto the center of each biscuit.
Working one at a time, pinch the sides of the roll upwards to seal the dough, and then roll into a ball. Place into prepared dish. Repeat with each remaining biscuit.
Combine the melted butter, Italian seasoning, and garlic powder in a small bowl. Lightly brush the butter mixture on top of each roll. Sprinkle Parmesan cheese over the tops.
Bake for 10-12 minutes, or until the rolls brown slightly on top and the dough is firm. Remove from oven and let cool slightly. Serve with pizza sauce, if desired.