Clean up your pot roast and cut into approximately 2 lb chucks. Cook on rack uncovered for a couple of hours to remove the fat. Remove to deep roasting pan and add “cream of mushroom soup” and fill the cans with water and add that as well. Try to keep the soup on top of the chunks of roast. Pour dry French Onion soup mix over this. Cover pan and bake at 300 for 6-8 hours.