Step 1

In a large bowl, combine beef, pork, egg, Panko, Parmesan, garlic powder, onion powder, allspice and nutmeg; season with salt and pepper, to taste. Using a wooden spoon or clean hands, stir until well combined. Roll the mixture into 1 1/4-to-1 1/2-inch meatballs, forming about 18-20 meatballs.

Step 2

Heat olive oil in a large stockpot or Dutch oven over medium heat. Add meatballs, in batches, and cook until all sides are browned, about 3-4 minutes. Stir in marinara sauce until warmed, about 3-4 minutes.

Step 3

Preheat oven to broil. Line a baking sheet with foil.

Step 4

Place dinner rolls in a single layer onto the prepared baking sheet. Place meatballs into rolls, about 3 per roll; top with cheeses.

Step 5

Place into oven and bake until the cheeses have melted, about 3-4 minutes.

Step 6

Serve immediately.