PREPARATION:

1. Trim fat from beef; discard. Cut beef lengthwise in half, then crosswise into 1/8-inch-thick slices. Combine 1 tablespoon teriyaki sauce and chili oil in medium bowl. Add beef and toss to coat; set aside.
2. Combine cornstarch, remaining 4 tablespoons teriyaki sauce and sherry in small bowl; stir until smooth. Set aside.
3. Heat wok over high heat about 1 minute or until hot. Drizzle 1 tablespoon peanut oil into wok and heat 30 seconds. Add half the beef mixture; stir-fry 2 minutes or until beef is barely pink in center. Remove beef to large bowl. Repeat with remaining beef mixture. Reduce heat to medium-high.
4. Add remaining 1 tablespoon peanut oil to wok and heat 30 seconds. Add mushrooms and onion; stir-fry 5 minutes or until vegetables are tender.
5. Stir cornstarch mixture until smooth and add to wok. Stir-fry 30 seconds or until sauce boils and thickens.
6. Return beef and any accumulated juices to wok; cook until heated through. Serve over pasta. Garnish as desired.