Dominating from start to finish, Pep Guardiola's side are now 17 points clear of second-place Manchester United with goals from Benjamin Mendy and Gabriel Jesus the reward for a commanding display at the King Power Stadium.
Four more wins from our remaining seven games and City will not be able to be caught.
Leicester set up to play as the away side, sitting deep and absorbing pressure in a bid to try and catch City on the counter-attack.
It's always a risky tactic to allow City great chunks of possession and Fernandinho almost made the hosts pay with just five minutes played as he drilled a 25-yarder into the bottom left corner, only for Sergio Aguero
to be penalised for running across Kasper Schmeichel's eye-line from an offside position.
Kevin De Bruyne then struck the crossbar from a free-kick on 23 minutes with Schmeichel again well beaten.
De Bruyne, Mahrez and Gabriel Jesus would go close again before the break, with the hosts offering nothing in attack until Jamie Vardy had an effort chalked off for offside with the last kick of a one-sided first-half.
The second-half took up where the first left off - City bossing possession, Leicester sitting back - until the 59th-minute when, finally, City broke through.
Mahrez saw a shot beaten out by Schmeichel and as a cross came back in from the right, the ball eventually fell to Mendy who shaped to shoot, cut inside Marc Albrighton's challenge and stroked a curling shot into the bottom right corner for a goal that gave the keeper no chance.
15 minutes later, City wrapped up victory with a move that showcased the sublime passing of De Bruyne who sliced the Foxes apart as he sent Jesus clear - the Brazilian squared the ball to sub Raheem Sterling who feigned a shot, checked back inside and then returned the pass to Jesus to prod home from six yards.
There was no further scoring as City played out the minutes that remained with little fuss.