thumb-sized piece ginger, peeled and finely chopped
4 tbsp tomato ketchup
4 tbsp hoisin sauce
4 tbsp golden caster sugar
2 tbsp dark soy sauce
2 tbsp rice vinegar
2 tbsp sunflower oil
Pickled carrot & mooli (see 'Goes well with')
4-5 spring onion, thinly sliced on the diagonal
6 tbsp wasabi mayonnaise (or 6 tbsp mayo mixed with 1 tsp wasabi paste)
Put the pork in a roasting tin, tip over all the marinade ingredients and massage it in with your fingers (or use a spoon) to coat the pork. Cover and chill overnight.
Heat oven to 160C/140C fan/gas 3. Cover the tin with foil and cook the pork for 31/2 hrs, basting every hour. Increase the oven temperature to 180C/160C/gas 4, remove the foil, baste the pork and continue to cook for 45 mins until it is beginning to caramelise around the edges.
Remove the pork from the tin and set aside to rest for 20 mins. Meanwhile, spoon away any fat from the tin and transfer the sauce to a small pan. Slice the pork – it will fall apart as you cut into it – then return to the tin. Warm the sauce in the pan, then pour over the meat and toss everything together. Spoon into the hot buns with the Pickled carrot & mooli, spring onions and a dollop of wasabi mayonnaise.