On Thursday night's Late Late Show, Corden, 43, told the story of how he acquired the sticky collector's item from Dion after Adele shared it during her 73 Questions with Vogue video, calling it her "proudest possession."
"It's pretty amazing," Adele, 33, said in the video. "James Corden — who's a friend of mine but also does Carpool Karaoke, which I did — did one with her. He knew how much of a fan I was of her and he made her spit her gum into a piece of paper and he framed it for me."
Replaying the clip on his show, Corden looked around to the audience and assured the crowd, "That is a true story," before recounting what happened.
Axelle/Bauer-Griffin/FilmMagic; Arturo Holmes/MG21/Getty; Charles Sykes/Bravo/NBCU Photo Bank via Getty Image
"The weekend before we had shot [Carpool Karaoke], we went on a little weekend away to Mexico, my family, [Adele], her son and we spent a weekend together," he explained. "And the following Friday I was shooting the Carpool with Céline Dion and Adele just loves Céline Dion."
Corden said that Adele and Dion had only crossed paths once and the "Easy on Me" songstress was just "starstruck by her." So, right before he and Dion embarked on their car ride, Corden asked for Dion's piece of gum. He explained that Dion was looking for something with which to throw it out and Corden quickly ripped a piece of paper from a script and handed it to her.
"I ripped off a piece and she put it in and I said, 'Don't. I'll do it,' because, you know, she was about to do the fold," he said. "I said, 'I got it, I got it, I got it.' I then had to give it to [show producer Diana Miller] and I was like, 'I need to keep this super safe!' And she took it and looked at me like, 'I think this is the day he's lost his mind.' "
RELATED VIDEO: Adele Says She's in a 'Strong Place Now' After Upcoming Album 30 'Was Bloody Hard to Make'
"And I said, 'Please keep it safe,'" he continued. "And then I gave it to [Adele] for her birthday. She's a difficult person to buy for. A candle doesn't cut it!"
The silly story comes weeks before Adele is set to release her album 30 on Nov. 19. The LP — which features single "Easy on Me" — is set to touch on her divorce from Simon Konecki.
"I was certainly nowhere near where I'd hoped to be when I first started it nearly three years ago," she wrote about the record. "Quite the opposite actually. I rely on routine and consistency to feel safe, I always have. And yet there I was knowingly – willingly even, throwing myself into a maze of absolute mess and inner turmoil!"