Creating Mac and Cheese Meatloaf Casserole is straightforward when you follow these simple steps:

1. Preheat your oven: Set your oven to 350°F (175°C) and prepare a 9×13 inch baking dish by greasing it lightly.
2. Prepare Meat Mixture: In a large mixing bowl, combine the ground beef and ground pork with breadcrumbs, milk, egg, garlic powder, onion powder, salt, and pepper. Mix until well combined.
3. Form the Meatloaf Base: Press the meat mixture into the bottom of the baking dish, creating an even layer.
4. Cook Macaroni: Prepare macaroni according to package instructions until al dente. Drain and set aside.
5. Combine Mac and Cheese: In a separate bowl, mix the cooked macaroni with 1 1/2 cups of cheddar cheese and marinara sauce. Stir well to combine.
6. Spread Mac and Cheese: Carefully layer the macaroni and cheese mixture over the meatloaf base, spreading evenly.
7. Top with Cheese: Sprinkle the remaining 1/2 cup of cheddar cheese and the grated Parmesan cheese over the top of the casserole.
8. Bake: Place the casserole in the preheated oven and bake for 45-50 minutes, or until the meat is cooked through, and the cheese is bubbling and golden.
9. Cool: Once done, remove from the oven and allow cooling for about 10-15 minutes before serving.
10. Slice and Serve: Cut into squares and serve warm.