Place the chopped scallion and ginger root in a small bowl. Add a cup of water to the bowl.
To a large mixing bowl, add the ground pork, white pepper powder, salt, and a whole egg.
Add the scallion/ginger infused water to the large mixing bowl. Squeeze the scallion/ginger to release extra juice to the mixing bowl.
Use one hand to mix everything in the mixing bowl continuously in one direction (clockwise or counter clockwise) for 5 mins until the mixture is uniform and sticky.
Scoop the mixture with both hands. Raise your hands about 12" above the mixing bowl. Drop the mixture with force into the bowl about 50-75 times. The mixture will be so sticky that it won't fall out when the mixing bowl turned upside down.
Heat the stock(water) in the stainless steel pot to boil.
Mix the starch with 3 tbsp of water in a small bowl.
Scoop some pork mixture with one hand. Wet the other hand with the starch soup. Toss the meatball between your hands to make it round. The meatball should be about the size of a toddler's fist.
Place the meatball into the boiling stock/water. Continue the process until the entire pork mixture is consumed.
Rinse nappa cabbage leaves, and put them on top of the meatballs.
Put the lid on. Bring the soup to boiling. Turn the heat to low and simmer for 2 hours.