Using a large stock pot, bring 4 litres (16.7 cups)of water to a boil.
Then add in the chicken or pork bones, reserved prawn shells and dried anchovies. Bring to a boil again.
Turn heat to low and cover with lid and simmer for 1½ hours.
Add salt to taste. Turn off the heat and set aside.
Pour the soup through a fine sieve before serving.
For cooking the choy sum:
Heat up a medium pot half filled with water and bring to a boil. Turn the heat to low and briefly blanch the choy sum for 2 minutes or until the choy sum turns bright green in colour. Drain and set aside.
For the filling:
Combine and mix well all the ingredients for the filling in a large bowl. Set aside.
For stuffing the wrappers:
Spoon some fillings onto the middle of each wrapper. Lightly wet the edges of the wrapper with some water around the whole wrapper square.
Fold the wrapper in half to form a triangle. Carefully press and seal the edges firmly together around the fillings. Press out any air trapped between wrapper and filling.
Place on a tray until ready to cook.
For cooking the wontons:
Heat up a large stock pot half filled with water and bring to a boil.
Cook the wontons in the boiling water on medium heat for 3 to 5 minutes or until wontons are just soft and float to the top of the water.
Serve the wontons with blanched choy sum and the soup prepared earlier.
Garnish with some sesame oil and ground white pepper.
If you want to freeze some of the wontons, place them on a large plate or tray and freeze in the freezer. Once frozen, store them in a ziplock bag in the freezer.