Cut steak into 6 serving pieces; place in a 3-qt. slow cooker. Combine the soup mix, soup and water; pour over beef. Cover and cook on low for 7-8 hours or until meat is tender. If desired, serve with mashed potatoes., Freeze option: Place beef in freezer containers; top with gravy. Cool and freeze. To use, partially thaw in refrigerator overnight. Heat through in a covered saucepan, stirring occasionally; add water if necessary.