Hirame (Japanese flounder) is widely distributed from the Kuril Islands to the South China Sea, and they are in season from September until they start to spawn in February. Kanbirame, the flounders caught in the depths of winter when the seas are at their coldest, have long been sought after. The slightly transparent and amber-tinted white flesh is firm and fatty, but without any overpowering flavor. It is both served as sashimi and used in all sorts of dishes, including nigirizushi.
The sweet aroma of the muscular fat found in the thin muscle of the dorsal fin, known as engawa, spreads across the palate, and very popular as a sushi menu. As flounder closely resemble halibut, the two are identified by placing them on their bellies; the head of the flounder will be to the left and that of the halibut to the right.