Barack and Michelle Obama were all smiles as they enjoyed a walk in the medieval village of Èze, France ... with Bono and The Edge. The group -- that BTW, also included Malia and Sasha -- headed to the 2 Michelin-starred gourmet joint, La Chèvre d'Or for lunch.

44 and the former First Lady are seriously living their best life right now. They were out with friends at another high-end restaurant in Provence where the former U.S. prez and his family are vacationing.

Barack and Bono, BTW, have a special bond. For starters ... Bono's global campaign and advocacy group, ONE, worked closely with Obama's administration during his 2 terms in office. But, the bond goes even more way back ... U2's "City of Blinding Lights" was heavily used in 44's 2008 and 2012 campaigns.

Barry O also walked out to that very track when he gave his emotional farewell address in 2017.