Wus Pork In Lettuce

Name: Wu's Pork In Lettuce
Ingredients: 2 heads boston lettuce or 1 large head iceberg lettuce; 6-8 chinese dried black mushrooms (can use shitake or baby portabellos); · boiling water to soak the dried mushrooms (if using); 1-8 oz can(s) water chestnuts, drained and minced; 1-8 oz can(s) bamboo shoots, drained and minced; 1 c celery, minced; 1 Tbsp ginger, minced; 2-3 clove garlic, minced; 1 1/4 tsp ground black pepper; 2 scallions both white and green parts for garnish; 2 Tbsp soy sauce; 2 Tbsp chinese rice cooking wine or dry sherry; 2 Tbsp cornstarch; 1 c chicken broth; 2 Tbsp peanut oil or vegetable oil; 1 lb ground pork