Cook the noodles in a large saucepan of boiling water for about 3 minutes, or according to the packet instructions, until just tender. Drain and set aside.
Mix together the cornflour, soy sauce, oyster sauce, rice wine and vinegar in a small bowl.
Spray a large nonstick wok or frying pan with cooking spray and heat over a high heat. Add the lamb and stir-fry for about 2–3 minutes until just cooked. Remove with a slotted spoon and set aside. Add the ginger, pak choi, spring onions and bean sprouts to the pan and stir-fry for 2–3 minutes until slightly softened.
Return the lamb to the pan along with the drained noodles, sauce mixture and the sesame oil and chilli oil. Toss together for about 1–2 minutes until heated through and serve immediately.