Step 1

Make the filling: In a large bowl, combine all the filling ingredients and mix until incorporated.

Step 2

Assemble the shumai: For each shumai, spoon 2 tablespoons of the filling into the center of a dumpling wrapper. Using a butter knife, press the edge of the wrapper in toward the center. Continue this around the circumference of the wrapper, indenting every ¼ inch.

Step 3

In a steamer (preferably bamboo) set over a pot of simmering water, steam the dumplings in batches, covered, until cooked through, 10 minutes. Transfer to a platter and serve with soy sauce and Chinese hot mustard on the side.