Place noodles in a large heat proof bowl; add boilng water. Let stand 10 minutes; drain.Cut beef into 2 x 1/4 inch slices. Cut onions into 1 inch pieces. Separate bok choy leaves from stems; rinse and pat dry. Cut leaves crosswise into 1 inch slices. Cut stems diagonally into 1/4 inch slices. Cut red pepper lengthwise into thin slices. Set aside.Combine broth, teriyaka, and cornstarch in a small bowl; stir until smooth.Heat the wok over high heat about 1 minute or until hot. Drizzle oil into the wok; heat 30 seconds. Add beef and stir fry until well browned. Remove beef to large bowl. Add bok choy stems; stir fry 1 minute. Stir in bok choy leaves and bamboo shoots; stir fry 1 minute. Stir cornstarch mixture until smooth; add to the wok. Cook until sauce boils and thickens. Stir in pepper and onions and heat 1 minute.Reduce heat to medium.Return beef and any accumulated juices to the wok. Add noodles and mix gently with beef and vegetables; heat through.Transfer to serving dish.