Place the Dried Shiitake Mushroom, Dried Wood Ear Mushroom and Dried Lily Bud in a bowl and cover with warm Water; soak 20–30 minutes until plump, then drain. Reserve and strain the soaking liquid, slice the shiitake, and shred the wood ear and lily buds.
Thinly slice the Pork against the grain and toss with 1 tbsp Shaoxing Wine, 1 tsp Light Soy Sauce, a pinch of Salt and 1 tsp Cornstarch. Let it marinate for 10–15 minutes.
Cut the Firm Tofu into thin strips or small cubes, slice the Bamboo Shoot into matchsticks, mince the Ginger, beat the Egg lightly, and slice the white and green parts of the Scallion separately.
In a large pot bring Chicken Stock to a gentle simmer with the reserved mushroom soaking liquid (if using) and the minced ginger. Add another splash of Shaoxing and 1–2 tbsp light soy sauce for depth.
Season the broth with a generous grind of Ground White Pepper and a pinch of Sugar. Add the marinated pork, rehydrated mushrooms and lily buds, bamboo shoots and tofu; simmer until the pork is just cooked through and the flavors meld, about 3–5 minutes.
Make a slurry of 2 tbsp cornstarch and 3 tbsp water, then slowly whisk it into the simmering soup until it thickens slightly to a silky, coat-the-spoon consistency.
Bring the soup to a gentle boil, then slowly drizzle the beaten egg in a thin stream while stirring the soup in one direction to create delicate egg ribbons. Turn off the heat as soon as the egg is set.
Finish by stirring in 1–2 tbsp Chinkiang Black Vinegar to taste and a few drops of Toasted Sesame Oil. Adjust seasoning with salt or a little more sugar if needed.
Ladle into bowls, scatter the sliced scallion whites and greens on top, and serve hot for a bright, warming bowl of classic hot and sour soup.
