Peel the large potatoes and slice them into uniform 1/4-inch rounds. Soak in cold water to prevent browning.

In a skillet, brown the ground beef over medium-high heat for 8-10 minutes. Drain excess fat and set aside.

In a mixing bowl, combine cream of mushroom soup and milk, whisking until smooth. Add onion powder, garlic powder, salt, and pepper.

Spray inside of the crockpot with cooking spray. Layer half of the potatoes, ground beef, half of the sauce, and cheese. Repeat layers, finishing with cheese on top.

Cover and cook on high for 3-4 hours, checking for doneness after 3 hours. Potatoes should be fork-tender and cheese melted.

Allow the casserole to rest for 10 minutes before serving. Stir to combine layers and enjoy!