1.Cook The Beef, Onion And Chili Powder In A 10-Inch Skillet Over Medium-High Heat Until The Beef Is Well Browned, Stirring Often To Separate Meat. Pour Off Any Fat. 2.Stir 1/2 Cup Soup In The Skillet And Cook Until The Mixture Is Hot And Bubbling. 3.Heat The Remaining Soup In A 1-Quart Saucepan Over Medium-High Heat Until Hot And Bubbling. Spoon The Beef Mixture Into The Taco Shells. Top With The Soup, Lettuce And Tomato.