The France international was pitted against his former employers after the defensive midfielder completed a £32m move to Chelsea from the Premier League champions in the summer transfer window.
Kante has already established himself as a first-team regular under Chelsea manager Antonio Conte and has started all eight of the west London side’s Premier League games so far.
The 25-year-old finished with 87 per cent pass completion and made three successful tackles during Chelsea’s dominant performance against Claudio Ranieri’s side.
Former Chelsea manager Vialli was particularly impressed with Kante’s display in Conte’s midfield.
“N’Golo Kante was splendid. He did the job perfectly,” Vialli told Sky Sports.
“He gives the team the right balance. He covers a lot of ground. He does well the simple things.
“He showed some skill with some killer balls. Overall it was a very solid and very effective performance.”
Kante played a key role in Leicester’s Premier League title triumph last season as the Foxes finished 10 points clear of second-placed Arsenal.
Chelsea will host Jose Mourinho’s Manchester United in their next Premier League fixture at Stamford Bridge on Sunday 23 October.
The Blues are in fifth place in the Premier League table and six points behind leaders Manchester City.
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