O–Toro comes from the bottom of the fish, cut from the outside just under the skin. It is streaked with fat, often half of it is fat.
It is the most expensive of the three cuts. There is not much of this area available on the fish, and it is not usually available during the summer months, as the fish is very active and uses up a lot of its fat.
If the fat is evenly distributed in the piece of O-Toro, it is called “Shimofuri.”
If the fat in the O-Toro is in strips that alternate with the meat, it is called “Dandara.”
O-toro means “big fat” in Japanese.