The first "American Idol" winner gets Ellen to spill her favorite guests and the funny reason she became a talk show host.
Ellen set up the desk for Clarkson -- complete with a matching mug, giant red button and opening sequence -- so she could practice for her hosting gig at the 2018 Billboard Awards on May 20.
"We decided she'd be a great talk show host, and I want her to be a talk show host," Ellen said. "And so we thought we would give you -- especially because you're so nervous about the Billboard Awards -- that we would give you a desk and you're going to interview me. It's your own show. It's 'The Kelly Clarkson Show.'"
Clarkson had only one critique: She wished the red button could eject a guest you didn't like, or make him or her go down a hole. She then launched into her first question.
"I don't know much about you. I don't know you at all, Ellen," Clarkson told the talk show host, or rather, her guest. "So my first question is, if you had to pick your favorite person that's ever come on this show, who would it be?"
Ellen said there's "so many people," but these were her picks: P!nk, Alicia Keys, Scarlett Johansson and Chris Hemsworth. Clarkson loved all of Ellen’s choices, especially P!nk: "Actually I think our love for P!nk is similar."
"When did you know you wanted to be a talk show host? Because that's very different from just standing up and doing comedy," Clarkson asked next.
"When they offered it to me. I was like 'That's a good idea.' When I was growing up as a kid I loved talk shows," Ellen replied. "I watched Johnny Carson, and I watched you know all the talk shows that were on, David Letterman, and I always thought it would be a fun job. And I never thought I would do it until I ran out of jobs."
Before letting Ellen go, Clarkson announced it was Kelly's Karaoke time. The singer pressed the red button and her 2004 hit "Since U Been Gone" flashed on screen.
"I will be offended if you don't know this song," Clarkson joked. "So tough, angst."
No offense was taken, because Ellen didn't back down from singing along to the anthem. Mid-song, we also found out what it was that Clarkson wanted and finally got: "Wine!"