Preheat oven to 375°F. Line a baking sheet with parchment.
Unroll the dough and separate into 8 triangles.
Blot pepperoni with a paper towel to reduce excess oil.
Sprinkle each triangle with mozzarella, then add a few pepperoni slices near the wide end.
Roll up from the wide end to the tip. Tuck the sides slightly to seal in the filling.
Brush tops with melted butter. Mix Italian seasoning and garlic powder; sprinkle over rolls, then add Parmesan and red pepper if using.
Bake 10–12 minutes until puffed and deeply golden and cheese is melted.
Cool 3 minutes. Serve warm with heated pizza sauce for dipping.