1.5kg/3lb 5oz belly pork, with rind still on
570ml/1 pint pork or chicken stock (if available, otherwise water)
100ml/3½fl oz light soy sauce
75ml/2½fl oz Chinese rice wine
25ml/1fl oz rice wine vinegar
2 tbsp demerera (or light brown) sugar
10cm/4in piece of fresh ginger root, peeled and sliced in rounds
a good pinch of dried chilli flakes
Cut the pork belly in large rectangular chunks (2.5x5cm/1x2in), put in a large pan, pour over enough boiling water just to cover, then bring back to the boil. Simmer gently for about 5 minutes, skimming off the scum that rises to the surface, then drain through a colander.
Rinse out the pan if necessary, return the pork to it and pour over enough boiling hot stock (if available) or water to cover it again.
Cut 5 of the spring onions in half and add to the pan with the soy sauce, rice wine, vinegar, sugar, star anise, ginger and chilli flakes. Cover tightly and simmer very slowly for about 2 hours, turning the meat occasionally, until the pork is very tender, soft and succulent.
Remove the pork with a slotted spoon and set aside. Strain the cooking liquid, ideally through muslin or a fine chinois, into a clean pan. Skim off as much fat as you can (but dont worry about leaving a little), then boil the stock hard to reduce and concentrate the flavours. It should be lightly syrupy and intensely aromatic, but don't over reduce as the soy sauce may make it very salty.
Thinly slice the remaining spring onions on the diagonal. Return the pork to the sauce and heat through.
Serve over plain noodles in a warmed soup bowl, with plenty of the sauce ladled over, and the sliced spring onions scattered over the meat.