Japanese Confectionery Yokan Jelly Types and Technique

Ingredients

• 500 g koshi-an, smooth sweet adzuki bean paste, sieved free of all skin fragments
• 150 g caster sugar
• 4 g kanten (agar powder), for neri-yokan (firm); reduce to 2–3 g for mizu-yokan
• 250 ml water, for dissolving agar; increase to 400 ml for mizu-yokan
• Optional — musha-yokan variant
• 100 g whole cooked chestnuts (kuri), kurizuka-cooked; added just before the mixture begins to set

Method

1. 1
   Combine the agar powder and water in a heavy saucepan. Bring slowly to 90–95°C, stirring continuously, until the agar is completely dissolved — no visible granules remain and the liquid is fully clear. This stage is critical: partially dissolved agar will produce a grainy texture in the finished block.
2. 2
   Add the caster sugar to the dissolved agar solution and stir until fully incorporated. Maintain the temperature at 90–95°C throughout — do not allow the mixture to exceed 95°C or drop below 90°C at this stage.
3. 3
   Remove the pan from direct heat. Allow the solution to cool slightly so that it no longer exceeds 90°C before adding the koshi-an. This is where the yokan lives or dies: if the agar solution is above 90°C when the anko is introduced, the residual heat breaks down the bean protein structure and the mixture separates; if it drops below 40°C before moulding is complete, the agar begins to gel in the pan and the block will not form cleanly. Fold the koshi-an into the agar-sugar solution in a steady, even motion until the mixture is perfectly homogeneous — no streaks of bean paste, no pockets of clear gel.
4. 4
   For musha-yokan only: distribute the whole cooked chestnuts through the mixture at this point, stirring gently once so they are evenly suspended. They should remain visible and whole when the block is sliced.
5. 5
   Pour the mixture immediately into a rectangular mould (yokan-bou form), lightly dampened with cold water. Work quickly: agar sets at 35–40°C and the operational window is narrow. Tap the mould lightly on the work surface to level the surface and expel any air pockets. The surface should be smooth and flat — no rippling or trapped bubbles.
6. 6
   Allow the yokan to set at room temperature until firm, then refrigerate for a minimum of 48 hours. Aged yokan (hiyashi yokan) develops a firmer texture and deeper flavour than freshly set yokan. The block is ready when it holds a perfectly clean edge under a moistened knife — the cut face should be smooth, dense, and without drag.
7. 7
   Unmould the block and slice with a moistened knife into precise geometric pieces. The firmness of correctly made neri-yokan allows clean, sharp edges. Wipe and re-moisten the blade between cuts. Serve in small portions alongside bitter matcha.