Preheat your oven to 350°F (175°C).

Grease a 9x13-inch baking dish with non-stick spray or butter.

In a skillet over medium heat, cook the ground beef and chopped onion until the beef is browned and the onion is soft, about 5-7 minutes. Drain any excess grease.

Season the beef with garlic powder, onion powder, salt, and black pepper. Stir well.

Layer half of the sliced potatoes at the bottom of the greased baking dish.

Spoon the beef mixture evenly over the potatoes.

Layer the remaining sliced potatoes over the beef.

In a bowl, mix the cream of mushroom soup and milk until smooth. Pour over the layered ingredients.

Sprinkle shredded cheddar cheese evenly over the top.

If desired, sprinkle paprika over the cheese.

Drizzle melted butter over the top.

Bake for 1 hour or until the potatoes are tender.

Let the casserole cool for a few minutes before serving.