Place steak in freezer until partially frozen for easier slicing.On a cutting board,slice beef,crosswise of grain,into 1/4" wide strips. In a 10" skillet or wok over high heat with 3 tsp. hot oil,cook carrots and green bell pepper for 2 minutes,stirring quickly and frequently. Add snow peas;stir fry 2 additional minutes.With a slotted spoon,remove vegetables to a plate. Add remaining oil,ginger,garlic and beef to skillet; stir fry until meat loses pink color,about 2 minutes. In a small bowl,blend cornstarch with soup;stir in vinegar and sugar.Gradually,stir into skillet;cook,stirring constantly until thickened. Return cooked vegetables to skillet;heat thoroughly.Serve over rice,if desired.Makes 2 servings.