Grated daikon goes over the noodles, juice and all. In some parts of Fukui the radish used is karami-daikon, a small round variety that sits buried in the soil and is genuinely hot, not merely peppery. The sharpness arrives on top of the smell of buckwheat and does not blend with it.

The usual account dates the dish to 1601, when a lord took up a post at Fuchu and brought a soba maker with him from Fushimi, near Kyoto. He is said to have encouraged the planting of buckwheat around the castle town as insurance against war and famine, and to have promoted eating it with grated radish. The soba maker he brought with him is named in the local accounts, which is unusual for a food this old. An emergency crop turned into the thing the province is known for.

Fukui still keeps a number of old local strains of buckwheat, grown on for generations in particular valleys. The grain is small and the flavour is concentrated. Most of it is milled slowly on stone, hull and all, which is why the flour is grey rather than white.

It is served cold, in summer and in winter alike, and no one offers you a hot version unless you ask. Cold, and hot at the same time, which is a combination that makes people order a second plate.