1️⃣ Preheat the oven:
Preheat your oven to 375°F (190°C). Lightly grease a 9×13-inch baking dish.

2️⃣ Prepare the meatloaf mixture:
In a large bowl, combine ground beef, breadcrumbs, egg, onion, garlic, milk, ketchup, Worcestershire sauce, salt, and pepper. Mix until fully combined but do not overmix.

3️⃣ Shape and bake the meatloaf base:
Press the meat mixture evenly into the prepared baking dish to form a flat layer. Bake for 25-30 minutes.

4️⃣ Cook the macaroni:
While the meatloaf is baking, bring a pot of salted water to a boil. Cook macaroni according to package instructions until al dente. Drain and set aside.

5️⃣ Make the cheese sauce:
In a saucepan, melt butter over medium heat. Stir in flour and cook for 1-2 minutes to form a roux. Slowly whisk in milk and cook until thickened, about 3-5 minutes. Stir in shredded cheese, garlic powder, paprika, salt, and pepper until smooth and creamy.

6️⃣ Combine macaroni and cheese:
Stir the cooked macaroni into the cheese sauce until fully coated.

7️⃣ Assemble the casserole:
Remove the partially baked meatloaf from the oven. Spread the macaroni and cheese evenly over the meatloaf base.

8️⃣ Finish baking:
Return the casserole to the oven and bake for an additional 15-20 minutes, or until bubbly and golden on top.

9️⃣ Garnish and serve:
Let cool for a few minutes, garnish with parsley, and serve warm.