Japanese Pork Belly in Regional Context: Kakuni, Buta no Kakuni Variations, and the Braised Pork Tradition

Ingredients

• 1 kg pork belly, skin-on, cut into 5–7 cm cubes
• For the braising liquid
• 500 ml dashi
• 200 ml sake
• 100 ml mirin
• 100 ml shoyu (koikuchi)
• 30 g sugar, approximately 2 tablespoons; increase for a more lacquered finish
• 1 piece kombu, cut into strips; served as accompaniment
• Nagasaki variation (optional)
• 15 ml Chinese dark soy sauce, 1 tablespoon per litre of braising liquid
• 1 star anise
• 4 eggs, hardboiled and peeled; added to braising liquid
• Okinawan rafute variation (optional)
• 200 ml awamori, replaces sake; higher alcohol requires longer initial cooking
• To serve
• plain steamed rice, short-grain; the definitive accompaniment

Method

1. 1
   Place the pork belly cubes in a large pot and cover with cold water. Bring to a full boil over high heat and hold for 5 minutes, skimming continuously. Drain, discard the water, and rinse each cube under cold running water, removing any grey matter or coagulated blood. The rinsed cubes should be clean and pale — any residual impurity will cloud the braising liquid and introduce bitterness.
2. 2
   Return the cleaned pork to the pot. Combine the dashi, sake, mirin, shoyu, and sugar and pour over the pork. Add the kombu strips. Bring the liquid to 85–90°C — a barely perceptible simmer, with occasional bubbles breaking the surface. This is where the dish lives or dies: a vigorous boil will toughen the lean sections and render the fat incompletely; only the slow conversion of collagen to gelatin at this restrained temperature produces the trembling, near-transparent fat that defines well-made kakuni. Maintain this temperature, adjusting the heat as needed, for 2 to 4 hours.
3. 3
   At intervals during braising, baste the pork cubes with the braising liquid using a spoon or brush, coating all surfaces. As the liquid reduces and concentrates, the sugar-shoyu compounds build on the surface of the pork. By the end of braising, each cube should carry a glossy, lacquer-like film — the visual signature of properly finished kakuni. Probe the pork with a skewer: it should pass through fat and lean alike with no resistance.
4. 4
   Remove the pot from heat and allow to cool to room temperature. Refrigerate overnight in the braising liquid. The fat will solidify on the surface and may be lifted away cleanly if a leaner finish is desired. The pork will have absorbed seasoning more deeply and uniformly than same-day service allows. The kombu strips, now saturated with rendered pork fat, are removed and reserved as an accompaniment.
5. 5
   To serve, slice the cold pork cleanly — chilled kakuni yields a precise cut that warm pork cannot. Arrange the slices in a pan with the reserved braising liquid and reheat gently, basting to restore and deepen the glaze. The surface should become fully glossy and the fat should return to translucency. Serve with plain steamed rice and the braised kombu strips alongside.