Place each thigh skin-down on a cutting board. Cut down the center to expose the bone. Cut along both sides of the bone, keeping the blade against the bone so you don’t waste meat. Slide the knife under to free the bone. Save the bones for banno-dare.
Trim any yellow fat and excess skin that hangs off the edges. Flip skin-side up and score the skin all over with the tip of the knife. The cuts let fat render and keep the skin from curling.
Pat the thighs dry with paper towels on both sides. Let them sit at room temperature for 20 to 30 minutes before cooking.
Cooking (8 steps)
Place the thighs skin-down in a cold stainless or carbon steel skillet. Turn the heat to medium. For the first 1 to 2 minutes, press the chicken flat with a spatula to keep the skin in full contact with the pan.
Cook skin-down for 7 to 8 minutes without moving the chicken. Periodically blot the rendered fat that pools in the pan with a folded paper towel. You’re looking for kitsune-iro (“fox color”), a deep golden brown.
Flip to the flesh side and cook another 4 to 6 minutes. The chicken should be about 80 percent cooked at this point. Remove to a plate, skin-side up.
Return the pan to medium-high heat. Pour the tare into the center of the clean pan. It will bubble immediately as the soy sauce hits the hot metal.
Place the thighs back in the pan with the skin facing up to keep it out of the sauce. Begin spooning the tare over the skin repeatedly.
Watch the bubbles. Fine small bubbles mean the sauce is boiling but thin, so keep basting and don’t rush. Bigger bubbles mean the sauce is thickening, so pick up the basting pace.
When the bubbles reach 2 to 3 cm across, the sauce has real body. Keep basting until the tare visibly diminishes and coats the chicken like lacquer, then drop the heat to low.
The chicken is finished when about 1 to 1.5 tablespoons of tare remain in the pan and the skin reflects the light like varnish. The full glazing phase takes 3 to 8 minutes.
Rest and Serve (2 steps)
Move the chicken to a cutting board and rest for 5 minutes. Slice each thigh on the bias into half-inch pieces. Spoon any remaining tare from the pan over the sliced chicken.
Serve over short-grain rice with shredded cabbage soaked in ice water (drained and patted dry).