Preheat oven to 400 degrees F.
In a large bowl, add ground beef, egg, oil, cheese, breadcrumbs, garlic, salt, pepper, basil, and parsley. Mix to combine, gently tossing a few times with your hands. Don’t overmix – it will result in tough meatballs!
Spray a large baking dish with non-stick spray and add 2 cups of pasta sauce.
Roll beef into golf-ball-sized meatballs (about 3 tablespoons of beef), and press a cube of mozzarella in the middle. Seal the beef around the cheese and set in sauce.
Once all meatballs have been added, sprinkle additional cheese and breadcrumbs over top.
Bake for 30-35 minutes or until meatballs are cooked through.
Serve with additional sauce if desired, toasted slider buns, and a few slabs of mozzarella for topping.
