Preheat your oven to 350°F (175°C). Grease a loaf pan or line with parchment paper.
In a large mixing bowl, combine the ground beef, ground turkey, Italian seasoning, minced garlic, bread crumbs, eggs, chopped onion, Parmesan cheese, and salt and pepper. Knead gently with your hands until the mixture is well incorporated.
Shape the mixture into a loaf and place it in the prepared loaf pan.
Spread the marinara sauce evenly over the top of the meatloaf.
Bake for 50 minutes.
Remove the meatloaf from the oven and sprinkle the shredded mozzarella on top. Return to the oven and bake for an additional 10 minutes, or until the cheese is melted and bubbly.
Let the meatloaf rest for 5-10 minutes before slicing. Serve warm.
Enjoy!