Step 1

In a medium bowl, combine the chicken, 2 tablespoons water, 2 tablespoons of the cornstarch, and 1/3 teaspoon of the salt and stir to mix and coat the chicken well. Let stand for 10 to 15 minutes.

Step 2

In a large pot, combine broth, ginger, chiles, and white pepper and bring to a simmer over medium-high heat.

Step 3

Add the chicken along with any liquid or cornstarch in the bowl. Simmer for about 10 minutes.

Step 4

Add the tofu, both types of mushrooms, bamboo shoots, soy sauce, the remaining teaspoon of salt, sugar, vinegar, and sesame oil and simmer another 10 minutes or so.

Step 5

In a small bowl, stir together the remaining 2 tablespoons of cornstarch with 2 tablespoons of cold water.

Step 6

With soup bubbling, stir in the cornstarch mixture and simmer for a couple more minutes, until the broth thickens a bit.

Step 7

With the soup bubbling again, stir the soup gently in a circular motion while pouring the egg into the pot in a steady stream to create ribbons of cooked egg.

Step 8

Serve hot, garnished with green onions and chiles if desired.