The Nigerian stepped up from 12 yards and dispatched from the spot after he was fouled in a poorly-timed challenge from Nathan Ake after the defender's loose pass to help the Foxes to their second win at Wembley Stadium in the space of three months.
It was the perfect start to another campaign for Brendan Rodgers' side and has set the tone ahead of another exciting Premier League season.
Iheanacho continues goalscoring form
As last season's top goalscorer for the Foxes Kelechi Iheanacho's confidence has continued to rise and rise and once again, he proved he had ice in his veins as he took the responsibility of taking the penalty.
In any other circumstance, it would have been Jamie Vardy, but he had been substituted for Patson Daka at that point, leaving Iheanacho with the task of putting the ball in the back of the net.
The former Manchester City striker proved to be a real threat to his former employers as he pressed high to win the ball back, in by doing so he won his penalty.
The Nigerian saw City defender Ake take a poor touch before trying to lay the ball back to keeper Zack Steffen, only to have the ball taken away from him.
What followed was a rash challenge and a point to the spot before he took his time, picked his spot and thundered home in front of the Leicester faithful.
If the same scenario had happened 12 months before, you would have been hard pressed to find someone who believed he could finish the task, but that's testament to how hard Iheanacho has worked.
His importance to the team is growing by the day and his trophy-winning penalty is yet another achievement to add to the ever-growing personal accolades for the 24-year-old.
Amartey steps up to the plate
Upon his selection, there were plenty of question marks towards Daniel Amartey's inclusion from the start, however, he answered his critics in fine fashion with a stellar performance.
With the Foxes lacking in the defensive department following long-term injuries to Wesley Fofana and Jonny Evans, many expected Rodgers to drop Ndidi back to the centre-back position but his decision paid off.
Partnering alongside Caglar Soyuncu, the two helped to restrict their opponents to minimal chances, with many efforts only coming from distance and helped to deliver a real solid display from the defence.
It is widely expected that Leicester will look to move into the market to find more options at centre-back but should they fail in their pursuit, Amartey has proved he is capable of being called upon.
The challenge for the Ghanian now is to deliver the same type of performance on a more consistent basis for Leicester. Before his ankle injury almost three years ago, the versatile Amartey was starting to establish himself as a regular in the side but if yesterday is a sign of what's to come, it will only strengthen Leicester even more.
Another trophy for the cabinet
Many will argue that the Community Shield is nothing more than a glorified friendly, however, whatever people think, any trophy is a positive for any club.
In Leicester's case, it now completes the set and the Foxes have now won every domestic trophy there is on offer - a tremendous achievement for a side in League One as early as 13 years ago.
The East Midlanders also thoroughly deserved the victory too. From the very first minute they looked fitter, more motivated and determined than Manchester City did.
Showcasing their high-intensity style of play in both attacking and defensive situations, the Foxes looked structurally organised and had a clear game plan set in place to get the better of Pep Guardiola's side.
There were several performances as well which were vital to Leicester's win. At the full-back positions Ricardo Pereira looked back to his old best whilst Ryan Bertrand looked as if he had been a part of the side for years.
Whilst there is still a long way to go and the season has barely even had a chance to come alive, Leicester look like they are in a good place to try and spoil the 'Big six' party once again.