Ikeda Mitsumasa, lord of the Okayama domain, issued a frugality order: commoners were to eat one soup and one vegetable dish. The people of the domain found a loophole. Fish and vegetables buried inside sushi rice were not side dishes at all, since nobody was eating them alongside the rice. They were part of the rice. The argument is thin and it worked.

What came out of it is a shallow tub of vinegared rice with a dozen seasoned things mixed through it. Spring brings Spanish mackerel, bamboo shoot, butterbur. Autumn brings matsutake. Conger eel is glazed and grilled, the mackerel is cured in vinegar, shrimp and squid are simmered or boiled in salt water, and everything except the pieces saved for the top is cut small and folded in.

For a dish invented to satisfy a legal technicality, it looks remarkably cheerful. That is the part I keep turning over. A rule meant to make people eat less plainly produced the most decorated bowl in the prefecture, and the decoration has outlived the rule by three and a half centuries.

It still appears in a wide bowl at festivals, memorial services, and any day when guests are expected. The combination changes from house to house and valley to valley. At Okayama station a boxed version has been sold to travelers for more than fifty years. Nobody eating it is thinking about the order anymore.