Line steamer trays with parchment or cabbage leaves and set aside.
On a lightly floured surface, divide the dough in half.
Cover one half of the dough with a towel or plastic and roll the other into a rope about 10 inches long. Divide the rope into 8 equal pieces, covering with a towel.
Roll one piece into a ball and flatten into a circle. Gently roll out the edges, keeping the center slightly thicker. Try to get the edges thin enough to become translucent. Add 2-3 cubes of stock and about 1 tablespoon of the pork filling to the center of the circle, keeping 1/2-3/4 inch of the edge clear. Pleat the edges over the filling and pinch the tops together to seal, twisting gently. Repeat with remaining wrappers and filling. Cover the assembled ones with a towel to keep them from drying out.
Place the prepared dumplings in the parchment-lined steamer about 3/4 inches apart and 1 inch away from the edge.
Steam over boiling water at medium heat until the dumplings have puffed and become translucent, about 8 minutes.
Remove the steamer tray and place over a serving plate. Serve the Xiao Long Bao hot with the ginger vinegar dipping sauce, chopsticks, and a soup spoon.