Macclesfield Town 0 Leicester City 2
Former Lincoln winger N'Guessan capped his league debut with the winner as the Foxes got their Championship campaign off to the perfect start, coming from behind to beat Swansea 2-1 on Saturday.
And N'Guessan - who turned 22 on Tuesday - endeared himself to the Leicester faithful again at Moss Rose, converting from close range 12 minutes after the break.
Matty Fryatt - last season's top scorer with 32 goals - opened his account for 2009/10 to seal the win 18 minutes from time.
Leicester had the best of the first half exchanges but couldn't turn their pressure into shots on target. Steve Howard was the first guilty party heading wide in the 11th minute.
Howard went close again within a minute but, after Nicky Adams' corner had dropped loose in the box, the 33-year-old could only fire wide of Jon Brain's goal.
Matt Oakley went closest to breaking the deadlock in the 27th minute but the former Southampton midfielder's powerful strike came back off Brain's post.
The home fans finally had something to shout about nine minutes after the break when John Rooney had their first shot on target, but it was the visitors who quickly stamped their authority back on the tie.
First Adams went close from long range before the lively N'Guessan - who bagged 14 goals for Lincoln last season - pounced on a loose ball to slam home from close range on 58 minutes.
N'Guessan's strike stirred the home side and they might have hit back ten minutes later but Ben Wright's shot from close range was well saved by Chris Weale in the Foxes net.
And the Silkmen were made to regret that miss in the 72nd minute when Fryatt doubled the Foxes' lead and sealed their spot in the second round draw.