If you are using dried mushrooms, soak in warm water for 20 minutes. Drain, squeeze out any excess liquid, then coarsely chop the caps and stalks.
Heat a large pan or wok over a moderate heat and add the oil. Add the spring onions, ginger, garlic and shallots and stir fry for 1 minute. Stir in the carrots, celery, onions and leeks and cook for 5 minutes. Place