Heat the oil in the wok and add the chicken cut into thin shreds. Stir-fry for 2-3 minutes.
Meanwhile, cook the noodles in boiling salted water until just tender — about 6-8 minutes. Drain in a colander and rinse under hot water. Toss in the colander to drain and leave to dry.
Add the shredded Chinese cabbage and green onions to the chicken in the wok along with the soy sauce, pepper and sesame oil. Cook about 1 minute and toss in the cooked noodles. Stir well and heat through. Serve immediately.
Preparation takes about 10 minutes, cooking takes 6-8 minutes.
Pork may be used instead of the chicken. Add fresh spinach, shredded, if desired and cook with the Chinese cabbage.
Shanghai noodles are available in Chinese supermarkets and also some delicatessens. If unavailable, substitute tagliatelle or dried Chinese noodles.