at a canter
Done or accomplished with ease or minimal effort. (A canter is a smooth, steady gait, as of a horse, which is between the pace of a trot and a gallop.) He was in such better condition than his competitors that he won the race at a canter.
at a canter
without much effort; easily. British At a canter is a horse-racing metaphor: a horse has to make so little effort that it can win at the easy pace of a canter rather than having to gallop.