1 lb. top round steak, 1/2-3/4" thick
5 tbsp. vegetable oil
1 lg. onion, cut in wedges
1 can (8 1/2 oz.) water chestnuts, drained & sliced
1 green pepper, cut in squares
1 can (13 1/4 oz.) pineapple chunks, undrained
2 tbsp. ketchup
1 tbsp. wine vinegar
2 tbsp. soy sauce
1/2 tsp. sugar
1 tbsp. cornstarch
3 tbsp. cold water

With sharp knife, cut beef into thin slices. In large skillet heat 3 tablespoons oil until hot but not smoking, quickly brown beef over heat, stirring rapidly 3-4 minutes. Remove meat and pan drippings to platter. Heat remaining 2 tablespoons oil in same skillet. Add onion, water chestnuts and green pepper. Stir fry until tender crisp, about 3 minutes. Add undrained pineapple, ketchup, vinegar, soy sauce and sugar. Heat to boiling.

Mix cornstarch smoothly with cold water. Add to sauce in skillet and heat, stirring, until sauce clears and thickens. Return meat and drippings to skillet; heat through. Serve over hot cooked rice.