Awesome Crockpot Pot Roast 2 (10.75 ounce) cans cream of mushroom soup 1 package dry onion soup mix 1 1/4 cups water 1 (5 1/2 pound) pot roast In crockpot, combine soup, soup mix and water. Place roast into crockpot. Coat with soup mixture. Cover. Cook on high for 3 to 4 hours, or on low for 8 to 9 hours.