Diego Costa's seventh goal of the season sent Chelsea into cruise-control - as fallen champions Leicester played like relegation candidates.
Goals from Costa, Eden Hazard and Victor Moses were scant reward for Chelsea's dominance as Claudio Ranieri's hapless troops were battered again - having now conceded 13 times in four Premier League away matches.
With Leicester lacking any of the defensive organisation, energy and self-belief which propelled them to the title, Chelsea dominated the vast majority of the match.
Costa was afforded acres of space to fire home as Leiceter's defence went AWOL at a seventh-minute corner. Then a blunder from Rob Huth allowed Pedro to play in Hazard, who rounded Kasper Schmeichel to score.
And a cute back-heel from Nat Chalobah, making his his home league debut for Chelsea as a sub, allowed Victor Moses to drill home the third ten minutes from time.
David Luiz also hit a post with a free-kick and Moses forced an excellent save from Schmeichel when the outstanding N'Golo Kante led a swift breakaway.