Re-hydrate the Dried Shiitake Mushroom (1) by soaking it in water for 20-30 minutes. Set aside.
Pat dry the Tiger Prawns (0.5 pound) paper towels. Place the chopped prawns in a medium mixing bowl. Add in Corn Starch (1 teaspoon) and Salt (1/4 teaspoon).
Place the Ground Pork (0.5 pound) in a large mixing bowl add in Corn Starch (1 tablespoon), Ground White Pepper (1/2 teaspoon),Granulated Sugar (1/2 teaspoon), Shaoxing Cooking Wine (1 tablespoon), Light Soy Sauce (2 teaspoon), Fish Sauce (1 teaspoon), Sesame Oil (1 teaspoon), and Unsalted Chicken Stock (2 tablespoon).
Squeeze and mix the seasoned ground pork with your hands, then throw it against the mixing bowl until it resembles a paste-like consistency.
Wash your hands and do the same with the seasoned shrimps. Put the pastes into the fridge and prepare the remaining ingredients.
Finely chop the shiitake mushroom.
Put shrimp and pork paste in the mixing bowl, add the Scallion (3/4 stalk), Fresh Ginger (2 slice) and mushroom. Squeeze and mix the ingredients with your hands until blended. Remember to throw the paste against the mixing bowl!
Place a Dumpling Wrappers (20) on one hand. Scoop roughly 3/4 to 1 tablespoon of mixed paste on the wonton wrapper with a butter knife or the dull end of a spoon. Then, wrap it into a cylinder shape with an open top.
Place a parchment liner into the bamboo steamer, then place the Shumai on the liner. Close the bamboo steamer lid.
Place a steamer rack and pour one cup of water into an electric pressure cooker. Place the bamboo steamer filled with Shumai into the pressure cooker. Close lid and cook at High Pressure for 3 minutes.
Wait for another 5 minutes and do a Quick Release.
Remove the bamboo steamer from the pot and enjoy them immediately!