Preheat oven to 375°F (190°C) and grease a baking dish.
In a skillet over medium heat, cook ground beef until browned. Drain excess fat.
Add chopped onion and minced garlic, cooking until fragrant.
Stir in the cream of mushroom soup, milk, salt, pepper, Italian seasoning, and paprika.
In the prepared baking dish, layer half of the potatoes, followed by half of the beef mixture.
Repeat layers, then cover with foil and bake for 45 minutes.
Remove foil, sprinkle shredded cheddar cheese on top, and bake uncovered for 15 more minutes until bubbly.
Let it cool for a few minutes before serving with a dollop of sour cream.