Dredge steaks in flour and sear on all sides in shortening. Place steaks in ovenproof dish. Add enough water to cover the bottom of dish; add vinegar. Cover tightly and bake very slowly in 300ºF oven for about 2 hours, adding a little more liquid as necessary.
About 30 minutes before meat is tender, add celery, apple, carrot and onion. This mixture will flavor the gravy and add flavor to the meat.