The staff at Watch What Happens Live surprised their boss by taping a special episode in which the Bravo personality appeared as a guest — and BFF John Mayer took over hosting duties.
Cohen, who turns 50 on Saturday, gasped as the “New Light” singer strolled into the Bravo Clubhouse.
“It is so hard to go dark on Andy because we talk so constantly. I couldn’t give away that I was in New York. It was the hardest 12 hours of my life,” said Mayer, 40.
The celebrations included cake, balloons, an embarrassing dive into Cohen’s vault of personal videos, a phone call from Dolly Parton and video messages from celeb pals Sarah Jessica Parker, Anderson Cooper, Kelly Ripa and Mark Consuelos.
Mayer even serenaded his friend with an acoustic cover of one of Andy’s favorite songs — “It’s My House” by Diana Ross. And the diva approves!
“Oh my God this is amazing!” Cohen sighed.
Mayer also joked about how being close with Cohen allows him entry into Hollywood’s A-list circles despite his dating history. (He’s romanced Katy Perry, Jennifer Aniston, Jessica Simpson and reportedly Taylor Swift.)
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“You have a lot of friends who without you would want nothing to do with me, and I find that exciting. You’re friends with Jennifer Lawrence, who just doesn’t want anything to do with me. And look at me. I don’t have the greatest track record when it comes to celebrity relationships, so it’s amazing to watch your friends humor me on a friend level but also keep a fair distance from me,” he said.
“It’s really, really fun. Because if you are somebody who cares about their image … dating John Mayer at this point is conceptually just sort of a no-no. So it’s really fun to get to hang out with your friends, your A-list star friends, who otherwise would be highly uncomfortable sitting around me. And I want to thank you for that.”
“Well I want them to see you in a ‘new light’ that I see you,” Cohen replied, riffing on Mayer’s new single.
“Thank you. Slowly but surely I’m setting myself up for another disastrous celebrity relationship so that I can wake up a month later and be back 10 years in time,” he said.
Later, Mayer joked about their bromance, asking Cohen, “Do you think people wonder if we’re in a secret relationship?”
“All my team does,” Cohen retorted.
To find out, tune in to Watch What Happens Live: Andy’s 50th Birthday airs Sunday at 10 p.m. ET on Bravo.