Preheat oven to 375 degrees Fahrenheit and line a baking sheet with parchment paper.

In a large bowl, add 1 pound lean ground beef, ¼ cup Italian bread crumbs, p¼ cup grated parmesan cheese, ¼ cup yellow onion minced, 2 teaspoons garlic, 1 egg, 1 teaspoon dried oregano, 1 teaspoon dried basil, 1 teaspoon salt, and ½ teaspoon pepper. Mix until everything is just combined.

Take about 1 ½ tablespoons of meatball mixture in your hand and start forming it into a ball. Take one piece of the diced 8 ounces mozzarella cheese, pop it into the center of the meatball, and continue to form a ball around the cheese. The meatballs should be 1 inch in diameter.

Place the finished meatballs onto the prepared baking sheet. Once the meatballs are all formed, place them in the oven and bake for 15-20 minutes, flipping halfway through.

While the meatballs are baking, cook the noodles according to the package directions. Remove the cooked meatballs from the oven.

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.

Remove the meatballs and sauce from the heat and serve with spaghetti noodles.