Preheat your oven to 375°F (190°C). Grease a 9x13-inch baking dish with olive oil or butter.

In a large skillet over medium heat, brown the ground beef along with the chopped onion until the meat is no longer pink. Drain excess grease, then add minced garlic, salt, pepper, and paprika. Stir until fragrant, then mix in the cream of mushroom soup and milk until smooth.

Wash and slice potatoes thinly (about 1/8 inch) for even cooking.

Layer sliced potatoes in the bottom of the greased baking dish, followed by half of the beef mixture and a sprinkle of shredded cheese. Repeat this process, finishing with a final layer of potatoes topped with cheese.

Cover the dish with foil and bake in the preheated oven for 60 minutes.

Remove the foil and bake uncovered for an additional 15-20 minutes until the cheese is golden and bubbly.