A hobikisen is a sailing boat that worked the waters of Lake Kasumigaura. It uses the principle of a kite: a very large sail catches the wind, the hull is pushed sideways across the lake, and a net is dragged through the water beneath it. The catch it was built for was shirauo and wakasagi.

Dozens of these boats out on the lake with their white sails open was, by all accounts, the thing the lake was known for. In the late 1960s the fishery moved over to trawlers and the sailing boats stopped working. In 1971 they came back as tourist boats, and three cities on the lake still run them from summer into autumn.

The dish comes from a different kind of surplus. Eel was caught here in quantity, and what could not be used was frozen, so that when a visitor arrived without warning something impressive could be put together quickly from a solid block.

Sake is brought to the boil, the eel goes in, and sugar and soy sauce cook it through. When the liquid is down by half the eel is lifted out and what remains is reduced and poured back over it. Then a bamboo leaf is set on the plate, standing for the sail. The boats stopped fishing sixty years ago. The leaf is still there on the dish.