Kelly Clarkson played "Plead the Fifth" on Watch What Happens Live Thursday night (March 5) -- and gave us a ton of interesting tidbits about her life! One of the most fascinating moments was when host Andy Cohen brought up allegations that Kelly called Miley Cyrus a "pitchy stripper."

"I never said 'Miley Cyrus,'" Kelly claimed. "The fact that I tweeted 'pitchy stripper' and people thought 'Miley Cyrus' is not my problem."

Andy also kicked it old-school with his questions, asking if the singer had a fling with American Idol runner-up Justin Guarini during the filming of From Justin to Kelly. Luckily for curious fans, Kelly gave everyone the scoop.

"We didn't date during Idol, which everyone thought we were dating," she said. "We did date during -- I feel like we weren't dating during the movie ... We did date a little bit."

Andy also asked Kelly whose Sound of Music performance was better: Carrie Underwood's or Lady Gaga's? Clearly, that's the toughest call ever, seeing as Carrie won the fourth season of American Idol and went on to have a massive country music career. Gaga, on the other hand, is one of the biggest pop stars in the world and received rave reviews for her 2015 Oscars medley.

"Well, those are completely different," Kelly said before diplomatically choosing Carrie "because she did the whole thing so I got to see a little bit more in depth."

Kelly's appearance on Watch What Happens Live is the latest stop on her Piece by Piece album promo run. She made headlines this week for her eloquent and all-around amazing response to a fat-shaming Twitter hater.

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