There is no sugar in the bean paste. It is seasoned with salt. Bite into it and the salt arrives first, and only behind it, slowly, does the sweetness of the adzuki and the pounded rice come up. It takes a moment to accept that an, the sweet bean paste at the centre of Japanese confectionery, can simply decline to be sweet, and that what is left is the flavour of the beans and the rice themselves.

It was made around Kuki and Kazo in eastern Saitama, at the time of the new rice, and it appears to date from the middle of the Edo period. Sugar was expensive then and ordinary households did not have it. What you cannot buy, you do without, and the recipe records that decision rather than apologising for it.

Sugar is applied at the table. You dip the cut face into it yourself, which reverses the usual order of things. Some houses grill the mochi first and add soy sauce instead of sugar. Some drop it whole into the New Year soup. Some fry both faces and pour honey over it.

Sugar became cheap a very long time ago, and almost every other confection in the country adjusted accordingly. The rice cake stayed unsweetened. Whether it becomes a sweet at all is left, deliberately or not, to whoever is eating it.