Creating the delicious Mac and Cheese Meatloaf Casserole can be done effortlessly by following these straightforward steps:

1. Preheat the Oven: Begin by preheating your oven to 350°F (175°C). This ensures it is ready to bake once you complete the prep work.
2. Cook the Macaroni: In a pot of boiling salted water, cook the macaroni according to package instructions. Drain and set aside.
3. Prepare the Meatloaf Mixture: In a large bowl, combine the ground beef, breadcrumbs, egg, Worcestershire sauce, garlic powder, onion powder, salt, and pepper. Mix until well combined.
4. Form the Meatloaf: Transfer the meat mixture into a loaf pan and shape it into a loaf. Leave some room at the top to add the mac and cheese later.
5. Make the Cheese Sauce: In a saucepan over medium heat, melt 4 tablespoons of butter. Stir in the flour and cook for about 1 minute until golden. Gradually whisk in the milk while simmering until the sauce thickens.
6. Add Cheese: Once thickened, stir in the shredded cheddar cheese until melted and smooth. Pour in the cooked macaroni, mixing until everything is well combined.
7. Layer the Mixture: Spoon the mac and cheese over the meatloaf in the pan, spreading it evenly. Sprinkle the grated Parmesan cheese on top for a delightful crust.
8. Bake: Place the loaf in the preheated oven and bake for 50-60 minutes or until the meatloaf is thoroughly cooked and reaches an internal temperature of 160°F (70°C).
9. Cool: Remove the casserole from the oven and allow it to cool for 10 minutes before slicing. This will help it hold its shape.
10. Garnish: Serve hot, garnished with chopped parsley if desired.

These easy steps will guide you in creating a delightful casserole that is bound to impress!