Hebo means the larvae of the black digger wasp. In the Tono region of eastern Gifu and the hills next to it, people go up into the woods in autumn, when the nests have grown to their full size, and dig them out. Some hunters take a small nest in June instead and raise it through the summer at home until it is worth harvesting. Either way the work is patient and the yield is small.

What comes out of the comb is simmered in sugar, soy sauce, and sake until it is dark and sweet-salty, a preparation called kanroni. That much can be eaten on its own with rice on the side. For hebo meshi the simmered larvae are cooked together with the rice and more soy sauce, so the grains take the color and the flavor all the way through.

A document from the Edo period records that in the old provinces of Mino and Shinano, wasp larvae were seasoned with soy sauce and mixed into rice. The practice is at least that old, and probably older than anyone bothered to write down.

The reason is geography. This is a landlocked place, a long way from any coast, and protein was not something you could simply go and buy. So the larvae were not a curiosity or a dare. They were the good thing, the dish you set in front of a guest you wanted to honor.