01 -
Preheat oven to 190°C (375°F).
02 -
In a large bowl, combine ground beef, Italian sausage, onion, garlic, bread crumbs, eggs, Parmesan cheese, Italian seasoning, and parsley. Add milk, salt, and pepper, then mix thoroughly until ingredients are fully incorporated.
03 -
On a baking sheet, shape the meat mixture into a rectangular loaf approximately 23×30 cm (9×12 inches).
04 -
Create a well in the center of the meatloaf and fill with shredded mozzarella cheese, chopped spinach (if using), and a spoonful of marinara sauce.
05 -
Carefully fold the meat mixture around the filling, ensuring edges are well sealed to form a cohesive loaf shape.
06 -
Spread marinara sauce evenly over the top of the meatloaf and sprinkle with grated Parmesan cheese.
07 -
Bake for 45-55 minutes, or until the internal temperature reaches 71°C (160°F).
08 -
Allow the meatloaf to rest for 10 minutes before slicing to keep juices intact.
09 -
Slice and serve with additional marinara sauce if desired.