Seeking a third consecutive win for the first time since October, the Blues got off to a fast start, netting with just 11 minutes on the clock.
A partially-cleared Ben Chilwell corner eventually dropped to the left-back, who struck cleanly on the volley through a crowd of bodies to beat Danny Ward.
João Félix came within inches of adding a second, clipping his chipped effort off the far post after some excellent close control in the build-up.
The Foxes looked for a response through Kiernan Dewsbury-Hall, but his deflected shot from range looped onto the crossbar with Kepa Arrizabalaga rooted to the spot.
Graham Potter then thought his side had doubled their lead when Félix swept home an incisive team move, but VAR ruled the goal offside.
Just five minutes later, Leicester took full advantage as Patson Daka capitalised on an error in judgement from Félix and buried an effort from the edge of the box.
However, parity wouldn’t last long as Chelsea restored their lead on the brink of HT with a delicate Kai Havertz flick lobbed Ward from an inventive Enzo Fernández lobbed pass.
Chelsea survived a goalline clearance after the break, before Brendan Rodgers introduced a triple change in search of a second equaliser.
Yet another offside goal kept the Foxes in the contest as Mykhailo Mudryk was denied his first Premier League strike, but the Ukraine international had the last laugh as his cushioned header set up Mateo Kovačić on the volley to double the lead for Potter’s men.
Wout Faes received a second yellow card late on to leave Leicester a man down as Chelsea saw out a well-deserved away victory that moved them to within five points of the top five.
Flashscore Man of the Match: Kai Havertz (Chelsea)
