Preheat the Oven:

• Preheat your oven to 350°F (175°C). Grease a 9×13-inch baking dish.

Cook the Ground Beef:

• Heat 1 tablespoon olive oil over medium heat.

• Sauté the chopped onion until softened (about 5 minutes).

• Add the ground beef and cook until browned, breaking it apart as it cooks. Drain excess fat.

• Season with garlic powder, paprika, salt, and pepper.

Prepare the Potatoes:

• Thinly slice the peeled russet potatoes evenly for consistent cooking.

Make the Creamy Sauce:

• In a bowl, whisk together the condensed cream of mushroom soup and milk until smooth.

Layer the Casserole:

• Arrange a layer of sliced potatoes at the bottom of the prepared dish.

• Top with half of the beef mixture, half of the creamy sauce, and 1 cup of cheddar cheese.

• Repeat with the remaining potatoes, beef, sauce, and cheese.

Bake the Casserole:

• Cover with aluminum foil and bake for 1 hour.

Finish Baking:

• Remove foil and bake an additional 30 minutes, until golden and bubbly.

Serve and Garnish:

• Let the casserole sit for a few minutes. Garnish with chopped fresh parsley and serve hot.