This is not uni-don. In a don, raw sea urchin is laid on top of rice. Here the urchin is cooked with the rice.

Kombu goes under the rice, the water is seasoned with sake and soy sauce, and just before it comes to the boil raw urchin equal to about a tenth of the weight of the rice goes in. Once it is cooked, the whole pot is stirred through thoroughly so that nothing sits on top.

Three kinds are landed along the Hagi coast, and each of them has its own few weeks in the year rather than a season shared with the others. Murasaki urchin in March and April, bafun urchin in June and July, aka urchin in July and August.

Sea urchin is expensive and did not appear on an ordinary table here. It came out when someone important was visiting, which is what makes this a dish of hospitality rather than of season. Around Hagi, and on the island of Mishima in particular, it is still made in houses and served in the island's eating places, sometimes with turban shell or abalone added to the pot. There is something almost defiant about it. The costly ingredient is not displayed on top where a guest can count the pieces. It is stirred away into the rice, where it can only be tasted.