Cut 10 cm Japanese leek (naganegi) (white part) horizontally to the core and peel off outer layers.
Press the layers flat on a cutting board and cut thinly in the same direction as the grain to make strings.
Place the strings of leek in a bowl of cold water for 10 minutes, then drain.
Measure out 4 tbsp water. Take a saucepan and add 1 tbsp turbinado sugar and about 1/3 of the water. Place the pan on the stove and heat on medium, swirl the pan around occasionally for even heating (avoid mixing).
Once it turns golden, add the rest of the water and swirl it around. (Be careful of splashing, protect your skin with oven mitts and long sleeves.)
Reduce the heat to medium-low and add the 1 ½ tbsp Japanese soy sauce (koikuchi shoyu), 1 tsp sake, 1 tsp mirin and 1 tsp honey.
Continue to heat until it reaches a thin syrup-like consistency, then turn off the heat and set aside for later.
Cut 300 g slab skinless pork belly into thick slices about 4-5mm thick (a little less than 1/4 inch).
Place it in a bowl and add 1 pinch salt and pepper and 1 tsp potato starch. Mix until evenly covered.
Heat a frying pan on medium-high, once it's hot, add 2 tsp cooking oil. Place the pork slices in the pan (try and keep it to one layer) and fry until golden brown on one side.
Flip the pork slices and use a piece of kitchen paper to wipe the excess rendered fat out of the pan.
Pour the sauce all over the pork slices.
Move the pork around in the caramel sauce and continue to heat until it has thickened and clings to the surface of the pork. Once done, remove from the heat.
Dish up 2 portions cooked Japanese short-grain rice in serving bowls and arrange the pork slices on top. Garnish with the shiraganegi, green peas (or edamame) and red pickled ginger (benishoga). Enjoy!
Notes
Choose fattier cuts like pork belly, shoulder, or butt for a juicier, beginner-friendly bowl; loin dries out fast without precise timing.
Stop the caramel at deep amber (≈320 °F / 160 °C); darker syrup turns bitter and masks the glaze’s sweetness.
You can blowtorch the glazed pork for 10 seconds to mimic charcoal aroma without a grill.
Storage: cool pork and sauce, store together, keep rice separate; refrigerate within 90 minutes and eat within 48 hours, or freeze uncooked pork plus sauce up to 1 month.