Trim fat off pork chops. Brown chops in oil in a heavy skillet. Drain off any fat. Mix 1 cup water to onion soup mix. Pour over the chops. Cover skillet and simmer until chops are tender (40-45 minutes).
Add evaporated milk and mushrooms to pan. Combine flour and 1/4 cup cold water. Blend into pan juices. Cook and stir under low heat until thick and bubbly. Sprinkle with parsley.