#Flatfish, such as sole and flounder, are usually cut into four fillets, two on either side of the central bones. The filleting technique is quite similar to that used for round fish.#
With the point of a filleting knife, cut around the edge of the fish to outline the shape of the fillets. With the point of the knife, cut the fish to the bone in a semicircle behind the head. “Hold fish steady to cut accurately with other hand”
Cut through to the bone, along the spine at the centre of the fish, in a straight line from head to tail. “Be sure filleting knife is sharp”
Keeping the knife almost flat, slip the blade between the flesh and the rib bones and cut away the fillet, using a stroking motion.
Continue cutting until the fillet and flesh lying along the fins are detached with the skin in one piece. Turn the fish around and slip the knife under the flesh of the second fillet. Detach the fillet from the bones as for the first fillet.
Turn the fish over and repeat the process on the other side. If the fish heads and bones are to be used to make stock, wash them thoroughly under cold water. “Keep blade as flat as possible” “Lift flesh away as you stroke knife along bones.”