Remove heavy membranes and veins from liver, if any. Cut into 4 x 1-1/2" strips. Dredge liver in flour and salt. Lightly brown in margarine or oil in skillet. Remover skillet; keep warm. Saute onion and green pepper (I used yellow, red, green and about a cup of bell pepper. Next time I will also add some mushrooms.) in skillet until onion is transparent. Add tomatoes with barbacue sauce. Bring to a boil. Add liver; heat thoroughly, about 10 minutes. Makes 4 servings.