Combine ground beef and Italian sausage in a large mixing bowl. Add breadcrumbs, shredded mozzarella, and grated Parmesan cheese. Mix well.
Add ½ cup of marinara sauce, egg, garlic powder, onion powder, oregano, basil, salt, and pepper. Mix until combined, being careful not to overmix.
Spread the remaining ½ cup of marinara sauce over the meat mixture, then roll it up into a log shape.
Place the rolled meatloaf seam-side down in a greased baking dish. Bake at 350°F for 60 minutes or until the internal temperature reaches 160°F.
Let the meatloaf rest for 10 minutes before slicing. Garnish with fresh basil leaves if desired.