Mix up hamburger, onion, garlic salt and pepper and make into patties (size is up to you). In a small to medium roaster. Put one layer and cover with layer of potatoes, I like a lot of potatoes so I put a good amount. Add one more layer of patties and one more of potatoes. Mix soup and 1 cup of water and pour over mixture. Place lid and cook for about 1hr-45 min or until you can smell the hotdish.