In a small bowl with warm water, soak shitake mushrooms until softened. Using hands, squeeze liquid and then mince.
In a bowl, combine ground pork, shrimp, mushroom, ginger juice, soy sauce, salt, sugar, and pepper until well-distributed.
In a bowl, combine corn starch and water, Stir until cornstarch is dissolved and add to pork mixture.
Mix pork mixture until very sticky.
Separate wrappers into individual sheets. Spoon a heaping tablespoonful of meat mixture on the middle of the wrapper and then gather sides to form a "cup" around the filling. Repeat with the remaining mixture.
Arrange siomai in a single layer about 1/4-inch apart on steamer basket and steam for about 15 to 20 minutes or until cooked through. Gently remove from steamer and serve hot with dipping sauce.
In a small bowl,combine calamansi juice, soy sauce and chili garlic sauce.
Recipe makes about 30 pieces; nutritional info based on 5 shumai per serving.