Preparation: Wash and soak mushrooms in warm water for 30 minutes; shred. Wash and soak dried bamboo shoots in warm water for 1 hour; shred in 3 cm pieces. Slice pork butt into 3 cm matchsticks. Wash and trim green onion, shred on the bias into 3 cm pieces. Soak rice stick noodle in warm water until soft. Cooking Soup: In sauce pan, heat broth. When it reaches gentle boil, add pork, mushrooms, bamboo shoots, soy sauce and sugar; simmer 10 minutes. Add soaked rice stick noodles; simmer for another 10 minutes. A minute before removing from heat, add vinegar and sesame oil; stir. Remove to serving bowl; garnish with shredded green onions. Serve.