Preheat the oven to 350°F (175°C) and line a baking sheet with parchment paper.

In a skillet over medium heat, add olive oil and sauté chopped onions and minced garlic for about 5 minutes until translucent.

In a large mixing bowl, combine ground beef, breadcrumbs, Parmesan cheese, and sautéed onion and garlic. Add parsley, basil, eggs, marinara sauce, Italian seasoning, salt, and pepper. Mix gently.

Shape the mixture into a rectangle about 1 inch thick on parchment paper.

Spread mozzarella cheese and optional slices of pepperoni or prosciutto across the center.

Roll the meat mixture tightly using the parchment paper, encasing the fillings.

Place the rolled meatloaf seam-side down on the prepared baking sheet.

Pour marinara sauce over the top and bake for about 60 minutes or until the internal temperature reaches 160°F (70°C).

Let the meatloaf rest for 15-20 minutes before slicing.