Japan — kakuni (角煮) from Nagasaki Chinese influence; the square cut refers to the pork preparation style
Kakuni (角煮, 'square simmered') is Japan's canonical braised pork belly preparation — thick squares of pork belly (skin-on, approximately 4×4cm blocks) slow-cooked in sake, soy sauce, mirin, and sugar until the pork reaches complete softness and the sauce becomes a thick, glossy reduction. The Chinese influence is direct: kakuni is considered a Japanese adaptation of Chinese red-braised pork (dongpo pork), and the name references the square cut of the pork pieces. Unlike the Okinawan rafute (which uses awamori and brown sugar), mainland kakuni uses sake and white or brown sugar with a typically stronger soy component. Production sequence: the pork belly slab is cooked whole in plain water first for 60–90 minutes (pre-cooking stage removes excess fat and firms the protein structure for cleaner final braising); the cooked whole slab is cooled and cut into precise squares; the squares are then braised in the final sauce over very low heat for 60–90 additional minutes. This two-stage cooking achieves: maximum fat rendering without over-drying the lean protein; clean, unmuddled braising liquid that concentrates into a pure glossy sauce. The fat in properly made kakuni is gelatinous and barely solid — almost liquid at body temperature. Garnish: a piece of soft-boiled or simmered egg (kakuni tamago), mustard (karashi) at table, blanched bok choy or spinach for colour and freshness.
Kakuni at its finest: the pork pieces barely hold together — the lean protein tender beyond expectation, the fat layer silky-liquid, the skin translucent and gelatinous; the sauce is concentrated to a deep mahogany sweetness with soy-sake depth; karashi applied cuts through the richness with nose-clearing clarity; one piece is a complete flavour world
{"Two-stage cooking: pre-cook whole in plain water (removes excess fat and odour), then braise in seasoned liquid — this order prevents muddied sauce","Skin-on pork belly: the skin's collagen converts to gelatin during braising, creating the characteristic thick, sticky sauce","Very low heat for the second stage braising — the gentle simmer converts collagen without toughening the lean muscle","Otoshibuta (drop lid) during braising: ensures even liquid circulation and prevents the squares from shifting and breaking corners","The sauce should reduce to a glossy, spoon-coating consistency — not watery soup","Overnight resting in the sauce: kakuni made one day and served the next has more deeply penetrated flavour and firmer fat texture"}
{"The pork pre-cooking liquid: some recipes use it as a base for the braising liquid after skimming; others discard it entirely — the clean approach is to discard and start fresh","Karashi (Japanese hot mustard) at the table: the clean, nose-clearing heat of karashi cuts the fat richness of kakuni brilliantly","Kakuni ramen application: a single piece of kakuni placed on shoyu ramen instead of standard chashu — the pork square creates a completely different eating experience","The scoring technique: some chefs score the skin of the pork block in a crosshatch pattern before braising — this allows the sauce to penetrate the skin layer","The sauce surplus: kakuni produces more sauce than needed for service; reserve it for eggs, tofu, or rice — it is extraordinary"}
{"Skipping the pre-cooking stage — braising raw pork belly directly in the seasoned sauce produces a murky, fatty sauce","Using lean pork instead of belly — kakuni requires the fat and skin for both flavour and the gelatinous sauce texture","Braising at too high temperature — the collagen converts to gelatin at 70–80°C; aggressive heat speeds the process but toughens the meat protein above this temperature","Not using an otoshibuta — without the drop lid, the squares in an inadequate volume of liquid cook unevenly","Serving immediately after cooking — overnight resting dramatically improves the flavour penetration and sauce quality"}
Japanese Cooking Reference; Braising Technique Documentation