Preheat the oven to 350°F.
Combine butter, Parmesan, garlic powder, parsley, oregano, salt and beaten egg in a small bowl. Brush half of this mixture onto the bottom of 10 x 15 pan. Set aside.
Remove rolls from packaging, and without separating them, use a serrated knife to slice in half horizontally. Place the bottom of the rolls into the prepared baking dish. Set the top of the rolls aside.
Add pizza sauce over the rolls, followed by shredded cheese and then pepperoni. Add the top of the rolls over this, then brush with the remaining butter mixture.
Tent a piece of foil over the rolls, making sure the foil does not touch the tops of the rolls. Bake for 20 minutes. Remove foil and continue baking for 5-10 more minutes.
Separate the rolls, and serve immediately.