Preheat the oven to 375℉. While it's heating, add the milk to a shallow bowl, then soak the bread slices in it for 5 minutes.
4 slices White bread, 1 cup Milk
While the bread soaks, combine the ground beef, ground sausage, garlic powder, Italian seasonings, Parmesan cheese, eggs, and breadcrumbs in a bowl, and give it a quick mix. Don't mix completely yet.
1 pound Ground beef, 1 pound Ground pork sausage, 2 large Eggs, ½ cup Parmesan cheese, ½ teaspoon Garlic powder, 1 cup Breadcrumbs, 1 tablespoon Italian seasoning, 1 teaspoon Dried basil, 1 teaspoon Dried oregano, ½ teaspoon Dried thyme, ½ teaspoon Dried rosemary, 1 teaspoon Dried parsley
Squeeze the milk out of the soaked bread, then shred the bread up and add it to the meat. Mix until fully incorporated, about 35-40 seconds. Don't over-mix!
Spray a 9-by-5 loaf pan with cooking oil, then form the meat mixture into a loaf shape and place it in the pan. If you don't want to stuff the meatloaf, you can skip step 5.
Optional: Using your fingers or a spoon, scoop a line into the middle of the meatloaf lengthwise, and add blocks of Mozzarella cheese. Cover the cheese up with the removed meatloaf.
½ block Mozzarella cheese
Top the loaf with tomato sauce and shredded Mozzarella cheese.
½ cup Tomato sauce, ½ cup Mozzarella cheese
Bake, uncovered, for 40 minutes, or until the cheese is golden and the meat reads above 165℉ with an instant-read thermometer. Remove, slice, and serve!