Chop the napa cabbage finely. Wash and drain well. Sprinkle 1 tablespoon table salt evenly over the cabbage. Toss / mix the cabbage to coat the cabbage with salt. Let it stand aside for 15 minutes.
Place the minced pork in a bowl. Add in the stock / water and mix well with a pair of chopsticks.
Wash the spring onions to get rid of the dirt. Chop off the bottom of the spring onions and chop the remaining into small pieces. Alternatively, use a pair of scissors to snip the spring onions into small pieces. You should end up with roughly about 1 cup of chopped spring onions.
Peel the old ginger and grate it finely, which should yield about 1 to 1.5 tablespoons of ginger. Peel and grate the garlic cloves as well.
By now the cabbage should reduce in size (wilted) and soften. Rinse to get rid of the salt and squeeze out the water thoroughly.
Add the chopped spring onions, grated ginger, grated garlic and cabbage into the minced pork. Add in the seasonings (white vinegar, sesame oil, soy suace and white pepper). Mix them well and cover with a clingfilm. Refrigerate for an hour for the flavours to combine.
Place a spoonful of the meat filling onto the dumpling skin. Wet the corners of the dumpling and wrap, making sure you seal the edges very tightly. At the end of the recipe is a video from where I learned how to wrap the dumplings. Place the wrapped dumplings on a plate dusted with corn flour. Do not place them too close to one another else they will stick to each other. Cover them with a damp tea towel. Keep the unwrapped dumpling skins under a damp tea towel as well to prevent the skins from drying out.
To freeze the dumplings: Place the wrapped dumplings on a floured plate and place it in the freezer for at least an hour. Transfer the frozen dumplings into a resealable ziploc bag and consume within 2 months.
Cooking the Dumplings
Boil half a pot of water.
When the water has come to a rolling boil, add in the dumplings (do not over-crowd them) and lower the heat to medium. When the water has return to a boil, add in a cup of cold water. Wait for the water to return to boil again, and add in a second cup of cold water. Let the water come to a boil and the dumplings should be cooked. This whole process will take about 5 minutes.
Rationale: The reason for this is to cook the dumplings more gently rather than boiling them straight for 5 minutes which may cause the dumplings to break. Thanks Bobbi for the advice!
To cook frozen dumplings: Do the same as above, just repeat for another time by adding a third cup of cold water and let the water come to a boil.
Serve
Use a slotted spoon and scoop the dumplings out. Place them on serving plates and serve with Chinese black vinegar and thinly sliced ginger.
NOTES
For more texture, add in 250 grams of peeled and chopped water chestnuts.