Strips of dried daikon are soaked to soften, cut small, mixed through natto and steeped in soy sauce, or in the sauce that comes packaged with the beans. After about a month the flavour has gone all the way into the centre of the radish. It is salty enough to work as a companion to a bowl of rice, as a topping for rice in green tea, or simply as something to have in front of you while drinking. It is served cold.

Mito built its natto industry on an early-ripening small soybean that could be got in before the typhoons came, a variety too small to be much use for tofu or miso. Natto made from the autumn crop was distributed to neighbours and to temples. What was left over after the distributing had to be made to last through the winter, and this is what the households of Mito worked out to do with it.

The name is a description of the look of it, and of nothing else. The shredded radish and the small beans run together into something that resembles minced meat, soboro.

The beans stay soft and the strips of radish stay crisp, and in the same bowl the two textures refuse to meet in the middle. Mixed together thoroughly, and not mixed at all.