Ndidi opened the scoring with only six minutes on the clock after his shot swerved away from Edouard Mendy and crossed the goalline via the inside of the post, capping off a clever corner tactic that looked to be straight from the training ground.
After a Chelsea penalty was overruled by VAR, the Foxes went straight to the other end and scored through a composed James Maddison.
Leicester could have added to their lead in the second half through James Justin and Youri Tielemans but the scoreline stayed at 2-0 come the final whistle, despite Timo Werner slotting the ball home only for it to be ruled out for offside.
Leicester's impressive record against 'big six' sides
The game against Chelsea was Leicester's final game against the 'big six' sides in the first half of the season and the Foxes' record in those games makes for impressive reading.
The East Midlands side have only lost one of the six games, a 3-0 defeat to Liverpool at Anfield, while they defeated Manchester City, Arsenal and Tottenham Hotspur away and drew with Manchester United at home before their victory over the Blues.
This record has seen them compete with those sides in terms of league placement and, should they continue their form against the 'big six', it will put them in good stead should they do the business against the other teams in the league.
Leicester do not miss Ben Chilwell
Ben Chilwell's £50 million move to Chelsea raised questions on the depth that Leicester have in the fullback positions but clever recruitment has meant that the Foxes have not missed the England defender and have thrived since his departure.
The young defender has not missed a minute of Premier League football this season and has established himself as one of Leicester's most consistent players. On top of that, Justin has propelled himself into the national team conversation, meaning that he may find himself competing for a place with his predecessor.
Maddison continues England push
Having only been capped once for England, Maddison will be determined to add to that solitary appearance and his performances will be putting him in a promising position to do so after scoring in his third consecutive game.
Maddison came up against one of his England rivals in Mason Mount and shone over his counterpart, creating chances for his side, hitting the crossbar with a weak foot shot and scoring Leicester's second goal at a crucial time in the game.
Should his performances continue, it would be hard for Gareth Southgate to omit the midfielder from his squad.