Start by peeling and slicing the potatoes into 1/4-inch rounds—aim for uniform thickness so they cook evenly. Set them aside in a bowl of cold water to prevent browning. While the potatoes soak, brown the ground beef in a large skillet over medium-high heat, breaking it apart as it cooks. Drain off excess fat once the beef is fully cooked and no longer pink, about 8-10 minutes. This prep work can happen simultaneously, so you're ready to layer everything quickly.

In a bowl, whisk together the cream of mushroom soup and milk until smooth and combined. Add the onion powder, garlic powder, salt, and freshly ground black pepper. Stir well to dissolve the seasonings evenly throughout the mixture. This sauce will coat all the layers and keep everything moist during the slow cooking process.

Lightly spray your slow cooker with cooking spray. Drain the potatoes from the water and begin layering: start with a layer of potato slices on the bottom, followed by some of the browned beef from Step 1, then pour some of the soup mixture from Step 2 over top, and sprinkle with shredded cheese. Repeat this layering pattern until all ingredients are used, making sure to finish with a generous layer of cheese on top. I like to reserve about 1/2 cup of cheese for the final topping so it gets beautifully melted and golden.

Cover the slow cooker and cook on high for 3-4 hours until the potatoes are completely fork-tender. Start checking around the 3-hour mark by piercing a potato slice at the bottom of the cooker—it should break apart easily with minimal resistance. The exact time depends on your slow cooker's heat intensity and potato thickness. I always cook on high rather than low because it ensures the potatoes fully soften without the dish becoming mushy.

Once the potatoes are tender, remove the lid and let the dish rest for a few minutes so the cheese on top can fully melt and set slightly. Stir gently to combine all the layers, breaking up any large potato pieces if needed, then serve directly from the slow cooker or transfer to a serving dish. The creamy potato, beef, and cheese mixture should be cohesive and comforting.