Stir first 4 ingredients in small bowl until sugar dissolves. Set sauce aside.
Season Steak with salt and pepper.
Heat 1 1/2 tablespoons oil in large wok over high heat. Add beef ; sear on both sides about two minutes until no longer pink outside. Transfer beef mixture to cutting board and let rest.
Heat remaining 1 tablespoon oil in same skillet. Add broccoli, yam, celery, garlic and ginger. Toss to coat; sprinkle with salt and pepper. Add sauce. Cover, reduce heat to medium-high, and cook until vegetables are just tender, about 5 minutes. Add beef mixture. Toss until sauce coats beef, and beef is to desired degree of doneness. Add noodles and toss until well coated. Serve immediately.