Prepare the Meatballs:
If using frozen meatballs, cook them according to the package instructions. If homemade, prepare and cook them now. Set aside when done.
Make Garlic Butter:
In a small saucepan over medium heat, melt the butter and add the minced garlic. Cook until fragrant and just starting to brown. Remove from heat and set aside to cool slightly.
Prepare the Sauce:
In a bowl, whisk together the sun-dried tomato pesto, marinara sauce, and olive oil. Set aside.
Preheat Oven:
Preheat your oven to 350°F (175°C) and coat a 9×13-inch baking pan with non-stick cooking spray.
Assemble the Rolls:
Hollow out the tops of each dinner roll with a sharp knife, creating a hole large enough to fit a meatball without puncturing the bottom.
Set the hollowed-out rolls in the prepared baking pan.
Add Garlic Butter:
Whisk the parmesan, dried parsley, dried oregano, and black pepper into the cooled garlic butter. Using a pastry brush, generously coat the inside of each hollowed-out roll with the garlic butter mixture.
Fill with Sauce and Meatballs:
Spoon about 1 tablespoon of the prepared sauce into each roll.
Place a meatball into each hollowed-out roll, followed by a spoonful of the remaining sauce mixture over each meatball.
Top with Cheese:
Evenly distribute the shredded mozzarella over the rolls. Sprinkle Italian seasoning on top.
Bake:
Bake in the preheated oven for 10-12 minutes, or until the cheese is melted and bubbly.
Serve:
Remove from the oven, slice between each roll, and garnish with chopped parsley if desired. Serve hot and enjoy!