- Preheat oven to 375F. Line a baking sheet with parchment paper to prevent sticking.
- In a large bowl, combine ground beef, breadcrumbs, parmesan cheese, onion, garlic, egg, oregano, basil, salt and pepper. Mix until everything is just combined.
- Take about 1 1/2 tbsp of your meatball mixture in your hand and start forming it into a ball. Take one piece of the diced-up mozzarella and put it into the center of the meatball. Continue to form a ball around the cheese.
- Place the finished meatballs onto the prepared baking sheet pan. Once the meatballs are all formed, place them in the oven and bake for 15-20 minutes, flipping half-way through
- In a large saucepan or pot, add the meatballs and marinara sauce. Cook over medium-high heat until the sauce is heated evenly and the meatballs are all coated in sauce.
- Serve and enjoy!