Slice Beef Into Very Thin Strips. Mix Cornstarch, Broth And Soy Until Smooth. Set Aside. Heat Oil In Skillet. Add Beef And Stir-Fry Until Browned And Juices Evaporate. Push Beef To One Side Of Skillet. Add Vegetables And Garlic Powder And Stir-Fry Until Tender-Crisp. Stir Cornstarch Mixture And Add. Cook And Stir Until Mixture Boils And Thickens. Serve Over Rice.