The tofu is not cut. It is crumbled in by hand, and then it and the daikon, carrot, burdock, taro and konjac are fried in sesame oil before any liquid arrives at all. The frying is what separates this from an ordinary clear soup, and you can smell it from the next room.

No meat and no fish go into it. Even the stock avoids them: no bonito flakes, no dried sardine, only kelp and dried shiitake. It is temple food and it observes the temple rules. What it does have, on account of the oil, is a body that a strict vegetarian broth would not otherwise get anywhere near.

There are two explanations of the name. One says it comes from Kenchoji, the great Zen temple in Kamakura, where the trainee monks made kencho-jiru and the word wore down in people's mouths over the centuries. The other traces it to a Chinese dish of chopped vegetables and tofu rolled in bean curd skin and fried, which arrived here with a school of temple cooking. The first is the one everybody knows.

It is a satisfying story, a soup named after a monastery. It is also unproven, and the second explanation has never gone away. Being widely known and being established are not the same condition, and this soup sits in the gap between the two.