Trim the mushrooms if necessary and tear any large ones in half. Heat a wok until just smoking. Add the vegetable oil and, when hot, stir-fry the asparagus for 1 minute. Add the mushrooms (except the enoki if using), garlic and ginger and stir-fry until fragrant. Deglaze the wok with the shaoxing, then add the sugar, soy sauce, sesame oil and chicken stock and allow the sauce to reduce slightly. Add the enoki, toss together and check for balance. Remove from the heat, fold in the bean sprouts and coriander and sprinkle with white pepper to serve.