In a small saucepan melt the butter, once it is hot and bubbly add the garlic and parsley. Cook stirring often until the garlic is soft and fragrant, 3-5 minutes. Remove the pan from the heat.
Preheat the oven to 350 degrees F. Line a large baking sheet with parchment paper, and set aside.
Place your uncut loaf of bread on a cutting board, then with a sharp knife, cut the bread 3/4 of way down into 1-inch diagonal slices. (see notes for how to cut your bread into bite-sized pieces!)
Place the cut bread on your prepared baking sheet.
Then use your figures to create some space between each slice, and drizzle the garlic butter into each space. It might seem like a lot of butter, but be sure to use all of it!
Carefully stuff the gap between each slice with pepperoni slices, I layered mine against one side of each slice to leave room for the cheese. Then stuff each slice with shredded mozzarella cheese. Be sure to leave a little mozzarella cheese to sprinkle on top of the bread!
Cover the loaf loosely with a large piece of aluminum foil, and place the bread in your preheated oven. And bake for 20 minutes.
After 20 minutes, remove the foil and layer any remaining slices of pepperoni over the top of the bread, then sprinkle the parmesan cheese and any remaining mozzarella cheese over the top. Place the bread back in the oven and bake for an additional 5 minutes or until the cheese on top is melted and the edges of the bread are golden brown.
I like to switch my oven to broil at this point to get the cheese on top extra melty and nicely browned, but you can easily skip this step!
Allow the bread to cool for 5 minutes before serving.
Serve with your favorite soup or pasta. Or as an appetizer with a side of your favorite marinara sauce, pizza sauce, or your favorite dipping sauce. Enjoy!