6 to 8 Servings
1 small head Napa cabbage, about 1 ½ pounds
2 large leeks, (about 1 pound) white and light green parts only, sliced lengthwise, rinsed, and drained
1½ tablespoons olive or canola oil
2½ tablespoons peeled and minced fresh ginger
6 to 8 ounces fresh shiitake mushrooms, stemmed and thinly sliced*
¼ cup rice wine or sake
14 ounces very firm tofu, halved crosswise and each half cut crosswise into ¼-inch slices
8 cups or 2 32-ounce cartons chicken or vegetable stock, preferably low-sodium
2½ tablespoons cornstarch mixed with ¼ cup water
4½ tablespoons Chinese black vinegar or Worcestershire sauce, or more to taste
3 tablespoons soy sauce, or to taste
1 teaspoon toasted sesame oil
¾ teaspoon freshly ground black pepper
1 teaspoon salt, or to taste
1 large egg, lightly beaten
1. Cut away the stem of the cabbage and discard. Cut the cabbage lengthwise in half, then cut each half lengthwise in half again. Cut each quarter into 1 ½ -inch sections, separating the leafy sections from the stem pieces, and place in a bowl. Cut each leek half into thin slices, about ¼-inch thick. Prepare all the ingredients and place near the stove.
2. Heat the oil in a large, heavy pot until hot, about 25 seconds. Add the leeks and ginger and stir-fry until fragrant, about 15 seconds. Add the tougher sections of the cabbage and the mushrooms and toss lightly over medium-high heat for 1 to 2 minutes, until slightly softened.
3. Add the rice wine or sake, partially cover, reduce the heat slightly and cook for about 5 minutes, until tender and dry. Add the leafier sections of the cabbage, the tofu slices, and the stock and bring to a boil. Lower the heat slightly and simmer for 15 minutes.
4. Slowly add the cornstarch and water mixture, stirring constantly to prevent lumps. Cook over medium-high heat until the broth has thickened, about 3 to 4 minutes. The soup should have the consistency of heavy cream. Stir in the black vinegar, soy sauce, sesame oil, black pepper, salt, and taste for seasoning, adding more soy sauce if necessary. Turn off the heat and slowly add the egg, pouring it in a thin stream around the circumference of the pot. Stir the soup several times. Ladle the hot soup into bowls and serve immediately.
*Shiitake mushrooms have a smoky, meaty flavor and are believed to strengthen the immune system and prevent tumors. They may also prevent heart disease by lowering cholesterol.
Variations:
Substitute 6 to 8 dried black or 1¼ ounces dried porcini mushrooms for the fresh shiitake. Rinse and soften in hot water to cover, reserving the broth. You can extend the broth with additional water and use in place of vegetable stock or add to chicken stock for extra flavor. Trim the stems or tough ends, discard, and use the caps as above.
