Spray a large nonstick wok or frying pan with cooking spray and heat over a high heat. Add the tofu and stir-fry for about 3–4 minutes until golden. Remove and drain on kitchen paper.
Mix together the oyster sauce, soy sauce, cornflour paste, rice wine and stock in a small bowl until smooth.
Wipe the pan clean with kitchen paper, re-spray with cooking spray and heat over a high heat. Add the ginger, spring onions, chilli, peppers and mushrooms and stir-fry for 3–4 minutes. Add the sauce mixture and bring to the boil, stirring constantly. Reduce the heat, return the tofu to the pan and simmer gently, stirring occaisonally, for 2–3 minutes.
Add the cooked noodles and toss together for about 1–2 minutes until piping hot. Serve in warmed bowls, garnished with sliced spring onion.