How to make it
Mix together sugar and salt in a bowl. In a roasting pan big enough to house the pork belly, rub the sugar mixture all over the belly and discard any leftover sugar mixture. Wrap the pan with plastic and place the pork belly in the fridge to marinate for 12 hours or so. Do not marinate longer than 24 hours.
When ready to cook belly, preheat oven to 450°F. Discard liquid that has accumulated in bottom of the pork belly pan. Put the pork in the oven fat side up and cook for 1 hour basting at 30 minutes until golden brown.
Turn down the oven temperature to 250 °F and cook another hour until the belly is tender but not falling apart. Remove from the oven and transfer to a plate.
When it’s cool enough, wrap the belly in foil and refrigerate until its chilled and firm. Cut cold belly into 1/2 inch thick slices that are 2" in length.
To serve heat a skillet over medium heat and cook slices in the pan until they are hot throughout. Once hot, use ¼ Lee Kum Kee Hoisin Sauce to glaze the pork belly.
Place hot slices of pork belly into warmed rice buns with ¼ Mayo and ¼ Lee Kum Kee Hoisin Sauce, cucumber slices, sliced scallions and julienned carrot (optional). Serve.