Preheat oven to 400°F.
Cut a large circle into the top of the bread loaf and scoop it out, forming a bread bowl. Cut the scooped out piece into cubes and reserve.
Over medium high heat, melt butter in a high-sided skillet. Add pepperoni and cook until brown, about 3-4 minutes. Add garlic, provolone and tomato sauce, and stir to combine.
Arrange bread bowl on a baking sheet and fill with pepperoni mixture. Bake for 25 minutes then add the bread cubes to the sheet tray and bake for another 5 minutes.
Serve bread bowl with bread cubes around it for dipping.