Hot and Sour Soup

Every good Chinese recipe has a good hot and sour soup recipe, it's one of those dishes that is common to all Chinese restaurants, and one can judge a restaurant on how tasty their soup recipe is, though I find the quality and flavour of the soups is variable. Most of the time it is thin, and I imagine quickly made with shortcuts. This original recipe, from Authentic Recipes from China by Kenneth Law, Lee Cheng Meng and Max Zhang, called for green peas, but we didn't have any, and I don't know that I have ever seen a Hot and Sour Soup with green peas as an ingredient in any restaurant. This recipe makes a much thicker soup that I am used to, with more chunks throughout, and tastes way better than the restaurant version. Some restaurant versions I have had are much spicier than this turned out, if you want it spicier, add the chili oil at the end, or even a little chili paste. The soup gets its sourness from the vinegar, but also from the tomato, so pick a good tasting tomato, and not a low-acid one.

Hot and Sour Soup
4 cups chicken or vegetable stock
1 tsp salt
1 tsp sugar
1/2 Tbsp grated ginger
1 large tomato, diced
8 oz (250 g) soft tofu, diced
4 large fresh shiitake mushrooms, diced, or 4 dried black Chinese mushrooms, soaked in warm water, stems discarded and caps diced
2 dried wood ear mushrooms, soaked in water and thinly sliced
2 Tbsp soy sauce
2 Tbsp black vinegar
1 tsp sesame oil
1/2 tsp freshly ground black pepper
1/2 tsp ground Sichuan peppercorns
2 eggs, beaten
2 Tbsp cornstarch blended with 2 Tbsp water
4 spring onions, diced
pinch of ground white pepper
chili oil, to serve
black vinegar, to serve

Bring the stock to a boil in a large pot. Add the salt, sugar, ginger, tomato, tofu and mushrooms. Return to a boil and simmer for 3 minutes.

Add the soy sauce, vinegar, sesame oil, black pepper and Sichuan peppercorns; stir to mix. Slowly add the beaten eggs into the soup, drizzling over the surface; let sit for 1 minute; do not stir.

Stir the cornstarch mixture, then pour slowly into the simmering soup while stirring gently. Keep on stirring until the soup thickens. Simmer for 1 minute more, then turn off the heat.

Serve hot, garnished with spring onions and white pepper. Add a few drops of chili oil and black vinegar, if desired.