1.Place noodles in large heatproof bowl, cover with boiling water, stand until just tender; drain.
2.Meanwhile, heat oil in wok; stir-fry garlic, chilli and mushrooms until mushrooms are just tender.
3.Blend cornflour with soy sauce in small jug. Add cornflour mixture to wok with pork, sauce and stock; stir until sauce boils and thickens slightly. Add noodles and onion; stir-fry until hot.