In a medium bowl, combine minced pork, chopped prawns, spring onions, soy sauce, Shaoxing wine, sesame oil, ginger, salt, white pepper, and egg white. Mix vigorously in one direction until the mixture becomes sticky. This ensures the filling binds well and stays juicy after cooking.
Place a wonton wrapper on your palm. Add about 1 teaspoon of filling in the centre. Moisten the edges with a little water, fold diagonally into a triangle, and press to seal tightly. Bring the two corners together and pinch to form the classic wonton shape. Repeat until all filling is used. Keep the finished wontons covered with a damp towel to prevent drying.
In a large pot, bring the chicken stock to a gentle simmer. Add the ginger slices and crushed spring onions. Simmer for 10 minutes to allow the flavours to infuse. Strain out the solids for a clear broth, then season with soy sauce and sesame oil.
In another pot, bring plenty of water to a boil. Gently drop in the wontons, stirring occasionally to prevent sticking. Once they float to the surface, continue cooking for about 3 minutes until fully cooked through.
Transfer the cooked wontons into the prepared broth using a slotted spoon. Allow them to simmer together for a minute so the flavours meld beautifully.
Ladle the wontons and broth into bowls. Garnish with finely sliced spring onions, coriander leaves, and a drizzle of chilli oil or black vinegar if desired.
Serve immediately while hot. The wonton skins are at their best when soft and delicate, complementing the light and savoury broth.