For Filling: Place Shrimp In Mixer. Mix For 2 Minutes. Add Salt And Sugar And Mix For 2 Minutes. Add Bamboo Shoots, Scallions And Egg Whites. Mix For 2 Minutes. Add Remaining Filling Ingredients And Mix For 5 Minutes. Place In Bowl And Refrigerate For 4 Hours. For Mushrooms: Soak Mushrooms For 1 Hour. Wash And Squeeze Out Excess Water. Remove Stems And Place In Heat Proof Dish. Toss Mushrooms With Salt, Sugar And Soy Sauce. Brush With A Bit Of Peanut Oil And Top With Scallions And Ginger. Steam For 30 Minutes. Sprinkle Mushrooms With Tapioca Flour To Bind The Filling. Pack Each Mushroom With 1 Tablespoon Of The Shrimp Filling. With Your Finger, Smooth The Filling And Press Down So That It Won'T Fall Out. Steam Or Pan Fry. Steam For 5 Minutes Or Fry Until The Mushroom And The Filling Turn Brown.