Chinese Steamed Mushroom Buns

1. Make dough: Dissolve yeast and sugar in warm water. Let stand 10 minutes. Add flour, knead until smooth (10 min). Let rise 3 hours until tripled. 2. Marinate: Combine marinade ingredients, spoon onto mushroom caps, marinate while dough rises. 3. Make filling: In nonstick pan, cook bell pepper, scallions, garlic 5-8 minutes. Chop marinated mushrooms, add with marinade and water chestnuts. Cook until liquid evaporates. Refrigerate. 4. Roll dough into 16-inch log, cut into 16 pieces. Flatten each into 3-inch circles. 5. Place heaping teaspoon of filling in center, gather edges and twist to seal. 6. Steam 8 buns at a time on cheesecloth-lined steamer for 15-20 minutes. 7. Serve with soy-vinegar dipping sauce.