Any cut of lean pork can be used to make this soup. Think of the meat as a condiment--use just enough for flavor and texture. Chicken can also be substituted, if desired. You can adjust the heat and sourness to taste by increasing or decreasing the vinegar and pepper.
4 dried Chinese (or shiitake) mushrooms
1/4 cup tree ears, optional
4 cups canned chicken broth
5 tablespoons rice wine vinegar
1/4 cup lean pork (from a center-cut pork chop), cut into julienne strips
1 block firm tofu (about 4 ounces), rinsed and cut into 1/4-inch cubes (about 3/4 cup)
1/3 cup matchstick-cut canned bamboo shoots, rinsed and drained
2 tablespoons cornstarch
1 large egg, well-beaten
1 teaspoon toasted sesame oil
1/4 teaspoon ground white pepper
1/8 teaspoon granulated sugar
2 tablespoons chopped scallions
How to Make It
In a small bowl, soak mushrooms in 1/2 cup hot water for 15 minutes. Drain and squeeze dry; reserve soaking liquid. Cut off and discard stems; slice caps thinly. In a small bowl, soak the tree ears (if using) in 1/2 cup hot water for 30 minutes. Drain and squeeze dry. Remove any hard spots, and roughly chop the tree ears. Discard the soaking liquid.
In a large saucepan, combine broth, 1 cup water, vinegar, and reserved mushroom liquid; bring to a boil over high heat. Add pork, mushrooms, tree ears, tofu, and bamboo shoots.
In a small bowl, whisk together the cornstarch and 3 tablespoons cold water. When soup returns to a boil, stir in cornstarch mixture, stirring constantly until soup is just thickened (about 30 seconds). Stir in egg, and remove from heat. Stir in the oil, white pepper, sugar, and scallions.