Powdered roasted tea goes into a cotton bag, the bag goes into boiling water and is drawn out again, and cold cooked rice goes into what is left. That is the whole of it.

It does not thicken. The Yamato version of this stays thin and loose, so that what sits in the bowl looks less like porridge than like rice floating in tea-coloured liquid. You drink it rather than eat it, and what stays behind in the mouth afterwards is only the smell of the tea.

People here call it okaisan, an ordinary affectionate word, because it was not a treat. It was breakfast, every day, for a very long time. The rites at Nigatsudo hall at Todaiji, which have been carried out every year without a break since 752, include records of something of this kind on the list of what the monks were given to eat. The men doing that observance are not eating well, and this is on the list precisely because it is thin.

An old compilation says it had already become an everyday food in Yamato in the eighth century. The everyday things are the ones that last, which is not what anybody expects. There is nothing impressive anywhere in this bowl, and that appears to be exactly why it is still here.