Preheat the oven to 375°F and line a baking sheet with parchment.
Place the ground beef, breadcrumbs, egg, minced garlic, dried oregano, dried basil, salt, and black pepper in a large bowl. Mix with your hands until the ingredients are evenly combined.
Divide the mixture in half. Press one half into a loaf shape on the baking sheet. Scatter the mozzarella cubes evenly over the center, leaving a small border around the edges. Cover with the remaining meat mixture and press the edges together to seal the cheese inside.
Bake for 45 minutes until the internal temperature reaches 160°F. Remove the meatloaf from the oven and spread the marinara sauce over the top. Return it to the oven for 10 more minutes.
Let the meatloaf rest for 5 minutes. Scatter the torn fresh basil over the top before slicing.