Elliot Anderson, with his first goal for the club, and Rayan Cherki were also on the scoresheet in a one-sided contest at the Etihad Stadium on Tuesday.
The Greek champions rallied early in the second half to cut the deficit to 2-1 through Stavros Palios but it was a rare moment of quality from the visitors.
City were superior in all departments even with a much-changed side as Enzo Maresca gave opportunities to fringe players.
Top scorer Erling Haaland, rested after an injury scare, remained rooted to the bench throughout.
Youngster Floyd Samba took the Norwegian’s place up front but the night was largely about Foden.
After two indifferent seasons and a frustrating start to the current one after his sending off in last month’s Manchester derby, the midfielder has returned in style in the past few days.
Rested: Erling Haaland
PA
His strike in Saturday’s victory over Ipswich was his first since last December and his treble marked his first Champions League goals in almost 12 months.
Were it not the the serious off-field situation hanging over the club, City’s routine win could have been described as business as usual.
Kervin Arriaga blasted over from an early attack but City soon established control and took the lead after 12 minutes through Anderson’s first goal for the club.
The England midfielder pounced from close range after Enzo Fernandez had clipped the bar from a free-kick.
Allan revelled in space down the left and, although one good run came to nothing, a second saw him cut inside and crack a fierce shot against the goal frame from a tight angle.
City doubled their lead in the 34th minute with a fine goal from Foden, who broke down the right and exchanged passes with fellow academy graduate Rico Lewis before lifting over goalkeeper Alberto Brignoli.
City wanted more and Fernandez went close early in the second half when he tried to pick his spot from distance but his effort was deflected wide.
AEK stunned City by pulling one back after 52 minutes. Substitute Zini tore down the left before feeding Pilios on his inside.
Hat-trick hero: Phil Foden
Getty
Pilios cut into the area and drove a powerful low shot past Donnarumma and into the far corner.
AEK’s vociferous supporters cranked the volume up even more but thoughts of an unlikely fightback were swiftly killed off as City claimed their third.
Foden was again involved, cutting the ball back for Cherki, but the goal was all about the touch and composure of the Frenchman.
Cherki shaped to shoot with his right foot but instead flicked the ball behind him and turned to finish in style with his left.
The fourth came moments later as Cherki picked out Lewis with a sweeping ball from halfway and his lay-off was calmly stroked into the roof of the net by Foden.
He completed his hat-trick 14 minutes from time when he arrived in the box to tuck home from Ryan McAidoo’s pass.