Lime flavored Ponzu and lime wedges add an extra bit of sour to this Hot and Sour Soup. Slideshow: More Asian Soup Recipes
In a small bowl, cover the lily buds with boiling water and let stand until softened, about 10 minutes. In another small bowl, cover the dried wood ear mushrooms with boiling water and let stand until softened, about 20 to 30 minutes. Rinse and coarsely chop.
In a large pot, heat the oil over moderately high heat. Add the garlic, scallions, ginger and pork and cook, stirring to break up the meat, until no pink remains, about 3 to 5 minutes. Add the stock and bring to a simmer. Measure out 1/4 cup of the stock and set aside in a small bowl. Add the lily buds, mushrooms, tofu, bamboo shoots, vinegar, ponzu, sesame oil, pepper and sugar to the pot and return the soup to a simmer. Using a circular motion, drizzle in the eggs and stir the soup gently until the eggs are cooked, about 30 seconds.
Stir the cornstarch into the reserved 1/4 cup of stock and then drizzle the mixture into the soup, stirring gently until slightly thickened, about 3 to 4 minutes. Taste and add more of the vinegar and ponzu if desired. Serve with lime wedges and chili oil.