Tochigi is wheat country. Double cropping is standard here, plateaus and second-crop paddies stretch right across the prefecture, and a great deal of wheat comes out of them, so wheat cooking has been perfectly ordinary here for a very long time indeed.

Komugi manju is a wheat dough wrapped around adzuki paste and then steamed. Because baking soda goes into the dough it is also called tansan manju, carbonate bun. The flour and the soda are sifted together, sugar water is worked into them until the dough is softer than an earlobe, and then it is filled and steamed until done.

The timing of all this is agricultural rather than religious. That year's wheat flour reaches the shops just before Obon, so Obon is when the wheat cooking happens: buns, udon, anything at all made of flour.

The first day of the seventh lunar month is called kamanofuta tsuitachi, the day the lid comes off the cauldron, when hell is said to open. The buns offered on that day were called kamanofuta manju, cauldron-lid buns. A sweet named after the moment when the door to the underworld swings open, made at that particular point in the year because the harvest had only just come in.