Toyokawa grew up as the town outside the gates of Toyokawa Inari, and inari sushi has been sold here for a very long time indeed, to people who had come all that way to pray.

The origin given for it is the early nineteenth century. Fried tofu pouches had been placed at the shrine as offerings, somebody thought to fill them with rice, and that became a kind of sushi. Toyokawa is counted, alongside Edo and Nagoya, as one of the three places where this may have started, and none of the three claims can be settled.

What it has become since is something else entirely. Around a hundred shops in the city now produce something in the region of three hundred different varieties between them, and the number keeps moving. Miso katsu on top. Eel on top. Wasabi inside. Five-ingredient versions.

That is no longer really a temple-gate food. It is closer to a permanent trade fair in which every shop is demonstrating what it can do inside a pouch of fried tofu roughly the size of a matchbox. A form that began as a way of eating what had been offered to a god has now split into three hundred separate directions, and the pouch of fried tofu is the only fixed point left in any of it.