The socket should be a hard wired appliance type socket mounted on the wall behind the appliance. Above this at the above counter level with other sockets should be a switched fused spur or a fused switch on a switch panel with other appliance switches. This way if the fuse should blow it's not on the appliance plug because there isn't one, the fuse would blow on one of the above places so that you can get to it easily. Anything else is just a bodge. Having the appliance actually plugged in to a non switched socket is also passable but not as good since you'd have to drag the appliance out if the plug fuse blew.