For the soup base: Heat a wok over high heat, add the oil, and stir-fry the ginger and mushrooms until softened. Add the chile, Shaohsing rice wine, hot vegetable stock, bamboo shoots, soy sauces, black rice vinegar and the white pepper. Bring the mixture to a boil, thicken with the cornstarch slurry and set aside over low heat.
For service: In some plastic pots, layer some of the cooked egg noodles with the raw bean sprouts, raw sliced baby corn, and spring onions. Top everything with the shredded chicken, and then spoon plenty of the soup base over the ingredients. Give the noodle pot or bowl a good stir, and serve immediately.
Can be found at specialty Asian markets.