- 1 1/2 pounds beef sirloin
- 1 tablespoon vegetable oil
- 3/4 cup salsa
- 1/3 cup ketchup
- 1 tablespoon brown sugar
- 1 tablespoon prepared Dijon-style mustard
- 6 (8 inch) flour tortillas
- Cut beef into thin strips. (Beef is easier to cut if partially frozen, about 1 1/2 hours.)
- Heat 12-inch skillet or wok over high heat. Add oil; rotate skillet to coat sides.
- Add beef; stir-fry 2 to 3 minutes or until brown; drain. Stir in salsa, ketchup, brown sugar and mustard. Cook and stir 1 to 2 minutes or until hot. Serve in tortillas with sour cream, shredded lettuce and chopped tomatoes, if desired.