1 kilogram piece boneless pork belly, skin on
1 teaspoon vegetable oil
5 cups water
1 teaspoon instant dashi powder
1 cup cooking sake
1 thumb-sized piece skin on ginger, thickly sliced
3 spring onions, root trimmed
¼ cup soy sauce
¼ cup brown sugar
1 tablespoon black or rice vinegar
1-2 teaspoons cornflour
1 tablespoon cold water
Umeboshi plum sauce
8 umeboshi plums, plain (Japanese pickled plums)
1 teaspoon soy sauce
1 teaspoon honey
1 teaspoon mirin
umeboshi plum sauce
Preheat the oven to 150˚C.
Cut the pork into 6 cm x 4 cm pieces and tie with kitchen string to prevent them falling apart during cooking.
Heat the oil in a large sauté pan and brown the pork on all sides except for the skin. Drain on kitchen towels to remove any oil.
Place in a single layer in a large ovenproof saucepan and add the water, dashi powder, sake, ginger and spring onions. Cover the meat with a piece of baking paper (not a lid) and bring to just below the boil.
Place in the oven and braise gently for 1½ hours or until tender when pierced with a skewer. Turn the pork pieces once during cooking. Add the soy, sugar and vinegar, cover with the baking paper and simmer for a further 30 minutes until the pork is meltingly tender. If making ahead, cool, cover and refrigerate at this stage.
Using a slotted spoon, remove the pork to a dish, cover and keep warm. Place the saucepan on the stove top and boil the braising liquid until reduced by half. If you want a thicker glaze, mix the cornflour and water until smooth then stir into the sauce. Bring back to the boil and cook for 2 minutes.
Umeboshi plum sauce: Remove the stones from the plums. Place the flesh in a shallow dish and crush to a rough paste. Mix in the soy, honey and mirin, adding a little more honey if you want it slightly sweeter. The sauce should be salty and tangy with only a hint of sweetness, as this counters the richness of the pork belly.