Lightly grease a plate with some sesame oil.
Place the shrimp into a stand mixer bowl and stir on low speed for 5 minutes using the paddle attachment.
Add lean ground pork, salt, tapioca starch, black pepper, cold water, Chinese mushrooms, sugar, and sesame oil. Stir for another 5 mins on low speed.
Take 3 pieces of dumpling wrappers, place them on the table and overlap them slightly.
Take about 1 tablespoon of filling and spread it across the middle of the 3 wrappers.
Lightly moisten the edges with water with your fingertips.
Fold each wrapper from top to bottom to resemble a half-moon shape.
Roll from left to right and seal the edges with water.
Place the dumplings upright onto a plate.
Repeat with the remaining filling.
Pour water into a large wok or pot and place the dumplings onto a steaming rack. Cover with a lid and steam over high heat for 15-20 minutes.
Serve while hot.