The 35-year-old, who departed the German giants in 2021, is a free agent following his release at Lyon at the end of last season.
But he could be set for a return to the Bundesliga champions to add to Thomas Tuchel's defensive options.
Boateng spent ten years at Bayern after joining from Manchester City in 2011 for £10million.
He left as a club legend, having made 364 appearances in all competitions, winning nine Bundesliga titles and two Champions Leagues.
And he could now be poised to add to his trophy collection with Bayern announcing he is back training with the first team.
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In a statement on Sunday morning, Bayern shared a picture of the 2014 World Cup winner in the club's training kit with the ball at his feet.
He joined the session alongside Thomas Muller and Eric-Maxim Choupo-Moting and other Bayern squad members who didn't start in Saturday's 2-2 draw at RB Leipzig.
The Bavarian outfit also stated that Boateng will continue to train at Sabener Strasse over the coming days.
According to Sky German reporter Florian Plettenberg, advanced talks are taking place between the club and player regarding a short-term contract.
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Should Boateng return to Bayern, he would be competing with Dayot Upamecano, Kim-Min Jae and Matthijs de Ligt for a starting spot.
And Boateng will also know Bayern will have a difficult time in winning the Bundesliga title for the 12th consecutive year - despite the signing of Harry Kane.
Tuchel's side currently sit third in the table following their draw against RB Leipzig, where they came from two goals down to nick a point.
Kane inspired the comeback, before Leroy Sane scored in the 70th minute.
The result leaves Bayern two points behind leaders Bayer Leverkusen, with Stuttgart a point ahead in second spot.