Brown pork chops in skillet with a little oil. Sprinkle with salt and pepper while browning. Place in crock pot. Sauté onions and mushrooms in skillet with oil until tender. Place in crock pot on top of pork chops. Pour 1 to 1 ½ cups water into crock pot. Cook on high for 4 hours. Place on serving dish. To make sauce pour one can cream of mushroom soup into a sauce pan. Add enough water from crock pot to get desired thickness.