In medium bowl, combine ground beef, onion and taco seasoning mix; mix well. Shape into 4 patties, about 1/2 inch thick.
Spray medium nonstick skillet with nonstick cooking spray. Heat over medium heat until hot. Add patties; cook 5 to 6 minutes or until browned on both sides, turning once. Drain if necessary.
Add salsa and barbecue sauce; mix well. Reduce heat to low; cover and simmer 10 to 12 minutes or until beef is thoroughly cooked, turning patties and stirring once or twice.