Preheat your oven to 375°F (190°C).
In a large mixing bowl, combine ground beef, breadcrumbs, eggs, chopped onion, minced garlic, Worcestershire sauce, salt, and black pepper.
Transfer the beef mixture to a greased baking dish and shape it into an even layer.
Bake the meatloaf for 25 minutes, then remove from oven.
While the meatloaf is baking, prepare the potatoes. Boil diced potatoes in salted water until fork-tender, about 15 minutes.
Drain the potatoes and return them to the pot. Mash them with sour cream, cheddar cheese, salt, black pepper, and paprika until smooth.
Spread the mashed potato mixture evenly over the partially baked meatloaf.
Return the casserole to the oven and bake for an additional 25-30 minutes, or until the meatloaf is fully cooked and the potato topping is slightly golden.
Let the casserole sit for 10 minutes before slicing and serving.