1 (1 ounce) package dry onion soup mix
1 1/4 cups water
5 1/2 pounds pot roast
In a slow cooker, mix cream of mushroom soup, dry onion soup mix and water. Place pot roast in slow cooker and coat with soup mixture. Cook on High setting for 3 to 4 hours, or on Low setting for 8 to 9 hours.