Not that we're keeping count, but Watch What Happens Live with Andy Cohen has been on for 18(!!), seasons and since the show's debut in 2009, Andy Cohen has interviewed just about everyone. Over the years, Andy has asked pretty much every kind of question you've ever wanted to ask those celebs. The Clubhouse has featured appearances from Real Housewives and Bravolebs to pop stars, politicians, movie stars, and, yes, even Oprah Winfrey.

And this week, Andy reflected a bit more about that iconic sit-down with Oprah from almost a decade ago during an episode of, well, WWHL. In a game called "At-Own It, Baby," played in the September 15 episode of WWHL, Andy was asked, "Andy, is there one question you've asked a guest that you now regret asking?"

His answer, featured in the clip above, was quite interesting. "You know, we were running out of time in the show, and I very flippantly asked Oprah Winfrey if she had ever swam in the lady pond, and it sounded so flip," Andy said. "And it just wasn't the time, and she was taken aback, and maybe that."

For those who need a refresher, Oprah made an appearance in the Bravo Clubhouse back in August 2013. Her appearance really, truly had it all, including a dazzling reenactment of a scene from Lee Daniels' The Butler in which she starred, Oprah singing Andy's name, and inside scoop on some of her legendary interviews, among other unforgettable moments.

You can check out some of those moments in the highlight reel, below.

Want more WWHL? Catch new episodes Sundays through Thursdays and catch up on the Bravo app.