Chicken soup doesn't need to take hours to make. This is a simple, light chicken soup that is richly flavored with shiitake mushrooms, and brightened with fresh ginger and soy sauce. The stock is very light, and comes just from the cooking of the ingredients for less than half an hour. But the combination of the ginger, chicken, mushrooms, soy sauce and a touch of salt and sugar is just lovely, and I highly recommend trying this soup. The recipe is an adaptation of one I discovered in a most curious cookbook, The Cultural Revolution Cookbook by Sasha Gong and Scott Seligman. One doesn't usually think of this rather painful period of Chinese history, when millions of Chinese urban youth, children of "intellectuals," were forced into the countryside to work as farmers, for its culinary legacy. But during this period, people learned to make do, and to create nourishing, satisfying food from simple, local ingredients.