In a large bowl, mix together the ground beef, ground pork, breadcrumbs, Parmesan cheese, parsley, onion, garlic, egg, milk, Italian seasoning, salt, and black pepper until well combined.
Transfer the mixture to a greased 9x5-inch loaf pan or shape it into a loaf on a parchment-lined baking sheet.
Spread the marinara sauce evenly over the top of the meatloaf for added flavor and moisture.
Place the meatloaf in the preheated oven and bake for 1 hour, or until the internal temperature reaches 160°F (70°C).
Once done, remove from the oven and let it rest for 10 minutes before slicing.
Slice the meatloaf and serve with extra marinara sauce on the side or over a bed of pasta for a hearty meal.
Notes
Let the meatloaf rest before slicing for better texture.