Preheat the Oven: Preheat your oven to 375°F (190°C). Grease a 9x13-inch baking dish with olive oil or non-stick spray.

Prepare the Ingredients: Peel and thinly slice the potatoes evenly. Chop the onion and shred the cheddar cheese.

Cook the Ground Beef: Heat 2 tablespoons of olive oil in a large skillet over medium heat. Add the ground beef and cook, breaking it up into crumbles, until browned. Stir in the chopped onion, garlic powder, paprika, salt, and pepper. Cook until the onions are soft. Remove the skillet from heat.

Layer the Casserole: Arrange a layer of potato slices on the bottom of the greased baking dish. Spread half of the cooked ground beef mixture over the potatoes. Sprinkle 1 cup of shredded cheddar cheese over the beef. Repeat the layers, finishing with a top layer of potato slices.

Prepare the Creamy Sauce: In a mixing bowl, whisk together the cream of mushroom soup and milk until smooth. Pour the mixture evenly over the casserole, ensuring it seeps into all the layers.

Bake the Casserole: Cover the dish tightly with foil and bake for 45 minutes. Remove the foil, sprinkle the remaining 1 cup of shredded cheese over the top, and bake for an additional 15 minutes or until the cheese is melted and bubbly.

Garnish and Serve: Let the casserole cool for a few minutes before garnishing with fresh parsley. Serve warm and enjoy!