Japanese Amanatto and Higashi: Sugar-Preserved Bean Confections

Ingredients

• 300 g kuromame (Tamba black soybeans) or azuki, or shiro-ingen (white kidney beans), sorted and rinsed; Tamba black soybeans preferred for their large size and thin skin
• For the progressive sugar syrup
• 1 litre water, divided across stages
• 900 g refined white sugar, divided; used in increasing concentrations from 30° Brix to 70–80° Brix across multiple stages

Method

1. 1
   Soak the beans overnight in cold water. Drain, cover with fresh cold water, and bring to a gentle simmer. Cook at a low, steady simmer until the beans are exactly al dente — slightly firm, with no raw starch at the centre, but with the skins entirely intact. Test by pressing a single bean between finger and thumb: it yields with gentle resistance and does not split. Drain carefully and cool to room temperature.
2. 2
   Prepare a dilute syrup at 30° Brix by dissolving approximately 150 g of the sugar in 500 ml of water over low heat, stirring until fully clear. Allow this syrup to cool completely to room temperature before use. Immerse the cooled beans in the cold syrup and leave undisturbed for 24 hours. The syrup must be cool at first contact — warm syrup at this stage causes bean cell structure to collapse.
3. 3
   This is the stage on which the dish lives or dies. Drain the beans, reserving the syrup. Dissolve additional sugar into the syrup to raise the concentration by approximately 10° Brix. Allow the enriched syrup to cool fully to room temperature. Return the beans to the cooled syrup. Repeat this cycle — drain, enrich, cool completely, re-immerse — every 24 hours, advancing the Brix by 10° at each stage until the syrup reaches 70–80° Brix. Do not advance while the syrup or beans retain any warmth; do not skip a rest stage. At each interval the syrup should be visibly more viscous and the beans progressively more lustrous.
4. 4
   At the final concentration stage, lift the beans individually from the syrup and arrange them on a wire rack or clean board in a single layer, ensuring no two beans touch. Leave in a cool, dry environment — not the refrigerator — until the surface dries to a thin, crystalline shell. The finished bean should be glossy and individually coated. The shell is done when it offers a brief crystalline resistance to the fingertip before the skin gives way.
5. 5
   Store in a cool, dry environment in a sealed container. Do not refrigerate without an airtight seal; ambient humidity softens the sugar coating. The finished amanatto is ready to serve as a confection, or to use as a topping for kakigori, mochi, or zenzai. The interior should be soft and moist; the shell, intact and crystalline.