Preheat oven to 425 degrees F (220 degrees C). Grease a 9x13-inch baking pan with cooking spray.
Remove biscuit dough from cans and flatten individual biscuits on a flat work surface. Stack pepperoni slices and mozzarella cheese cubes over biscuits. Pull the edges of each biscuit into the middle to cover the pepperoni and cheese.
Place rolls seam-side down in the prepared baking pan. Brush with beaten egg. Sprinkle Parmesan cheese, garlic powder, and Italian seasoning over rolls.
Bake in the preheated oven until golden brown, 18 to 20 minutes. Serve with warm pizza sauce for dipping.