1.Heat Oil In Medium Skillet Or Saucepan About 1 Minute; Add Onion. Cook Over Medium Heat 5 Minutes, Or Until Onion Browns A Bit, Stirring Occasionally. Blend In Chili Powder. 2.Add Shredded Pot Roast And Barbecue Sauce. Reduce Heat To Low And Cook About 5 Minutes Or Until Bubbling, Stirring Occasionally. 3.Fill Rolls Evenly With The Meat Mixture And Serve.