Yakitori Tare

In a small, heavy saucepan combine the soy sauce, mirin, sake, and sugar. Add the chicken bones or wings — these will render collagen into the tare as it reduces, giving it a glossy, lip-sticking body that plain soy-mirin reduction cannot achieve. Stir the sugar to distribute it. Set over medium heat and bring slowly to a simmer, stirring until the sugar has completely dissolved. You will notice the liquid becoming more fragrant as the sake alcohol begins to cook off, shifting from boozy to sweetly savory.

Maintain a steady medium-low simmer, uncovered, for 25–30 minutes, stirring occasionally. The liquid will gradually deepen from amber to a dark mahogany and the surface will shift from a lively rolling bubble to a slower, thicker, more reluctant boil as the sugars concentrate. Watch the sides of the pan: a ring of syrupy residue will form and darken — this is normal. Keep the heat low enough that it never boils hard, which can make the tare grainy. The tare is reduced enough when it has lost roughly half its original volume.

Remove the chicken bones with tongs and discard them — they've done their collagen work. Pour the hot tare through a fine-mesh strainer into a heatproof jar or container, pressing on any solids. Let it cool to room temperature; it will thicken noticeably as it cools to a consistency between maple syrup and molasses. Store in the fridge, where it keeps indefinitely. At service, reheat in a small saucepan or simply let it come to room temperature — cold tare is too thick to coat evenly. To use: dip skewers into the tare pot and return to the grill, repeating 3–4 times to build up layers of glaze.