Step 1: Cook Beef: In a skillet over medium heat, brown the ground beef and half a chopped onion for 5-7 minutes until no pink remains. Drain any excess fat and set it aside.

Step 2: Slice Potatoes: Wash and thinly slice the potatoes to approximately 1/8-inch thick.

Step 3: Layer Ingredients: In a greased crockpot, layer half of the sliced potatoes, then half the cooked beef mixture, and sprinkle 1 cup of cheddar cheese. Repeat the layers.

Step 4: Prepare Sauce: Whisk together cream of mushroom soup, milk, garlic powder, and salt and pepper in a bowl. Pour over the layered ingredients.

Step 5: Cook: Cover and cook on low for 6 to 8 hours until the potatoes are fork-tender.

Step 6: Finish with Cheese: In the last 15 minutes, sprinkle remaining cheddar cheese on top and cover again to melt.

Step 7: Garnish and Serve: Let sit before serving and garnish with fresh parsley or chives. Serve hot.