Kasube is the Hokkaido word for skate. Being a cartilaginous fish, its bones are soft, which means the whole thing can be eaten, flesh and skeleton together. What you get is meat with something firm and crunchy running through it.

The name has at least two explanations and neither is flattering. Before anyone had worked out how to cook it, this fish, which generates ammonia inside its own body, was avoided. Boil it or grill it and all you had was kasu, dregs. Hence kasube. The other account traces the word to Ainu, to kashumbe.

The cooking answers the objection directly. Cut it into chunks and simmer with sugar, soy sauce, sake, and mirin. Ginger in the pot keeps the smell down.

It is a winter fish here, appearing in supermarkets when the cold comes, at its best around December and January, and it is as likely to be eaten as an evening side dish as with a drink. The Ainu are recorded as having dried fish of this kind, pounded it, and eaten it with boiled wild plants, so it has been food here far longer than the insult in its name suggests. A fish named for being worthless has been on the table all winter, every winter, for as long as anyone here can remember.