Creating this Cheesy Ground Beef & Potato Casserole can be achieved by following these easy steps:

1. Preheat the Oven: Preheat your oven to 350°F (175°C) to get it ready for baking the casserole.
2. Cook the Beef: In a large skillet, heat the olive oil over medium heat. Add the chopped onion and ground beef, cooking until the meat is browned and the onions are translucent.
3. Season the Beef: Stir in the garlic powder, salt, pepper, and paprika. Mix well, allowing the spices to infuse with the meat. Set aside.
4. Prepare the Casserole Dish: Grease a 9×13-inch baking dish with cooking spray or a little extra olive oil.
5. Layer the Ingredients: Begin layering. Start with half of the sliced potatoes at the bottom of the dish. Follow with half of the cooked beef mixture and a third of the cheddar cheese.
6. Add Another Layer: Repeat the layering with the remaining potatoes and beef, finishing with the last third of the cheese.
7. Mix Soup and Milk: In a separate bowl, combine the cream of mushroom soup and milk. Stir until smooth.
8. Pour over Casserole: Pour the soup mixture evenly over the layered ingredients in the baking dish, ensuring all layers are covered.
9. Cover and Bake: Cover the baking dish with aluminum foil and place it in the preheated oven. Bake for 30-35 minutes.
10. Uncover and Finish Baking: After 30 minutes, uncover the dish and bake for an additional 15-20 minutes or until potatoes are tender, and the cheese is bubbly and slightly golden.
11. Garnish and Serve: Once out of the oven, let it sit for about 5 minutes before garnishing with fresh parsley. Now, it’s ready to be served!

By following these steps, you will create a satisfying and flavorful casserole that is both comforting and delicious.