1 pound beef round tip steaks, cut 1/8 to 1/4 inch thick
2 teaspoons vegetable oil
1 medium onion, cut into thin wedges
3/4 cup prepared barbecue sauce
4 crusty rolls, split

Stack beek steaks; cut lengthwise in half and then crosswise into 1-inch wide strips. Set aside.
In large nonstick skillet, heat oil over medium-high heat until hot. Add onion; cook and stir 3 minutes or until lightly browned. Remove from skillet; keep warm.
In same skillet, add beef (half at a time) and stir-fry 1 minute or until outside surface is no longer pink. (Do not overcook.) Stir in onion and barbecue sauce; heat through, stirring occasionally. Spoon equal amount of beef mixture on bottom half of each roll; close with top half of roll.