Combine all the ingredients for the dumplings, except for the water and the gow gee wrappers, and refrigerate for one hour.
Take one heaped teaspoon of prawn mix and place in the centre of the gow gee wrapper.
Moisten the edges with water and fold over the prawn mix so you have a half-moon shape. Pleat the edges and place on a tray lightly dusted with corn flour.
Prepare your steamer basket over the top of a pot of boiling water, making sure the steam basket doesn't touch the water.
Spray the basket with oil so the dumplings don't stick and steam with the lid on for 5 minutes. Serve straight from the basket with the black vinegar dipping sauce
For the dipping sauce, combine all ingredients in a bowl and lightly whisk together.