Celtic's young striker slammed home four goals in the first half at Airdrie's Excelsior Stadium.
But Beattie will not have netted a simpler hat-trick as the Killie defence self-destructed.
The forst goal came inside the first five minutes thanks to central defender Robbie Cochrane's hesitancy allowing Rocco Quinn to stab the ball inside the box to Beattie who stroked it past Graeme Smith with ease.
The second came less than a minute later when Garry Hay was caught in possession on the edge of his own box by Momo Sylla who reached the byeline and squared for Beattie to knock the ball home at the near post.
Cochrane's miserable afternoon continued midway throught the half when he missed a routine long ball. Again Beattie had only the keeper to beat and he kept his composure to volley past Smith to complete his hat-trick.
Kilmarnock, with James Fowler playing alongside Steven Naismith in attack, looked lively up front, but the final pass was constantly awry.
Smith produced a great save to deny Momo Sylla getting in on the act, before Beattie almost added a fourth with a thirty-five yard screamer which the keeper had to be on his toes to tip over. It was only delayed, however, as the stiker beat the offside trap and tiptoed into the box to fire home unchallenged.
Killie introduced Gary Wales at half time and should have gotr one back after the restart when Neil McGregor headed against the bar when it seemed easier to score after Celtic goalkeeper Rab Douglas completely missed Eric Joly's inswinging corner.
Although Douglas was busier in the second period, the visitors never looked likely to break through.