6 dried Chinese mushrooms
1 lb. fresh tofu
1 sm. can sliced bamboo shoots
1/2 lb. boneless pork, sliced thinly
6 c. chicken stock
2 tsp. soy sauce
1/4 tsp. ground white pepper
3 tbsp. Chinese black vinegar
2 tbsp. cornstarch
3 tbsp. water
1 egg, lightly beaten
Bouillon granules to season

Prepare ahead: In small bowl cover mushrooms with 1/2 cup of hot water, soak 30 minutes. Discard water. Cut away tough stems and discard. Thinly slice mushroom caps. Drain bamboo shoots and tofu, and rinse in cold water. Slice into strips.

Combine in heavy saucepan the stock, soy sauce, mushrooms, bamboo shoots. Bring to boil over high heat. Immediately reduce heat to low, cover pan and simmer 3 minutes. Drop in tofu, pepper and vinegar. Bring to boil again. Add pork and boil again. Mix cornstarch with water and pour into soup. Stir until soup begins to thicken, then slowly pour in egg, stirring all the while. Remove from heat, adjust seasoning with bouillon, vinegar and pepper.