Cut 680g of lean, skin-on pork belly into ¾in / 2cm thick pieces. Blanch in boiling water for about 1 minute, until opaque, then drain and rinse.
Heat 2 tablespoons of vegetable oil and 2 tablespoons of rock sugar in a wok over low heat until the sugar melts. Add the pork and cook until lightly browned.
Add ⅓ cup of Shaoxing wine and cook for 2 minutes. Stir in 2 tablespoons of soy sauce, 1 tablespoon of dark soy sauce, and 2 cups of water.
Cover and simmer for 45-60 minutes, until the pork is fork-tender. Stir every 5-10 minutes, adding water if it gets dry.
Uncover, raise the heat, and stir until the sauce reduces to a glossy coating.
