Preheat oven to 350˚F. Lightly spray a 9×11 inch baking dish with cooking spray.
Split the rolls in half horizontally and place the bottom halves into the prepared baking dish. Add half of the Provolone cheese and top with the shredded beef. Add the remaining Provolone and cover with the top halves of the rolls. Brush the rolls with melted butter, cover with aluminum foil and bake for 10 minutes or until the cheese is hot and bubbly. Remove the foil and bake for an additional 5 minutes or until tops are golden brown. Remove dish from oven, slice and serve.