This is Joanne Chang's recipe from Flour, Too, and it makes me want to see the rest of her recipes. It's easy, fast, and delicious. I've never had hot and sour soup that I liked before this, although I tried to like it several times. This recipe is a keeper, though.
Chang writes that she wrote the recipe with button mushrooms because they are easy to find, but suggests using wood ear mushrooms if you can get them. I will further suggest that if you use wood ear mushrooms, buy them dried and rehydrate them instead of using fresh ones. I have only used button mushrooms in this recipe, but I did once use fresh wood ears in a different soup recipe and they were very slimy the next day. I ended up removing them before eating the rest of the soup.
2 tablespoons vegetable oil
1 garlic clove
1 tablespoon peeled and minced fresh ginger
4 scallions, white and green parts, minced, plus 2 tablespoons chopped for garnish
8 ounces ground pork
4 cups chicken stock
One 1-pound block soft or firm tofu (not silken and not extra-firm), cut into 1/2-inch cubes
4 or 5 medium button mushrooms, wiped clean and thinly sliced
1 teaspoon granulated sugar
2/3 cup rice wine vinegar
3 tablespoons soy sauce
1 teaspoon freshly ground black pepper
1 tablespoon sesame oil, plus 2 teaspoons for garnish
1 tablespoon Sriracha sauce
2 large eggs
White pepper for garnish
In the saucepan, heat the vegetable oil over medium-high heat until hot. Add the garlic, ginger, scallions, and ground pork and cook, stirring occasionally, for about 1 minute. Break up the pork into smaller pieces but don't worry about breaking it down completely. Add the stock and bring to a simmer.
Add the tofu, mushrooms, sugar, vinegar, soy sauce, black pepper, sesame oil, and Sriracha sauce and bring the soup back to a simmer over medium-high heat. (Taste the soup. If you want it hotter, add more Sriracha sauce; if you want it more sour, add more vinegar.)
In a small bowl, whisk the eggs until blended. With the soup at a steady simmer, slowly whisk in the eggs so they form strands. Bring the soup back to a simmer. Divide the soup among four bowls and garnish each with a little sesame oil, scallion, and white pepper. Serve immediately. The soup can be stored in an airtight container in the fridge for up to 3 days.