In a skillet over medium heat, brown 1 pound of ground beef alongside 1 chopped onion for about 5–7 minutes until the meat is no longer pink. Drain excess grease and set aside.

Wash and slice 4 medium potatoes into uniform 1/8-inch thick rounds. Set aside.

In your Crockpot, layer half of the sliced potatoes at the bottom, then half of the browned beef mixture and 1 cup of shredded cheddar cheese. Repeat and finish with cheese on top.

In a mixing bowl, whisk together 1 can of cream of mushroom soup, 1/2 cup of milk, 1 teaspoon of garlic powder, 1/2 teaspoon of salt, and 1/4 teaspoon of pepper until well combined. Pour evenly over the layered ingredients.

Cover the Crockpot and cook on low for 6 to 8 hours. Avoid lifting the lid during cooking.

In the last 15 minutes, sprinkle an additional cup of shredded cheddar cheese on top and replace the lid until the cheese melts.

Once cooked, allow the casserole to cool for a few minutes before serving. Garnish with freshly chopped parsley or chives.