The comedian also told ET why she chose not to rap in the Apple Music series.
Just because Chelsea Handler is a fan of Blake Shelton's music, doesn't mean she won't crack a few jokes at his expense.
ET's Kevin Frazier caught up with the 42-year-old comedian at the launch of Carpool Karaoke: The Series on Monday night in West Hollywood, California, and she revealed what it was really like to have a singalong in the car with the country crooner while filming the new Apple Music show. "I love Blake Shelton. He's one of my favorites," Handler confessed, adding that she listened to his latest album to determine the songs they'd sing while on Carpool Karaoke. New episodes of the show stream Tuesdays on Apple Music.
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While she praised his tunes, Handler went on to call out Shelton's ego. "He's a narcissist," she joked. "[Blake] made me listen to all his albums and then act like I hadn't heard them dozens and dozens of times -- which obviously nobody has."
As for why she chose to sing with a country music singer on Carpool Karaoke instead of a rapper like, say, her ex-fling, 50 Cent, Handler quipped, "I think I've done rap."
"I can't rap," she added. "That's insulting to the whole entire rap community."
When asked what her go-to rap song would be, Handler joked that "it's too obvious." Taking the bait, Frazier teased that her rap track must be 50 Cent's "In Da Club."
Last year, Shelton appeared on Handler's Netflix show, Chelsea, and praised his girlfriend, Gwen Stefani, for helping to bring him out from "rock bottom" following his divorce from Miranda Lambert.
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"My marriage fell apart," the 41-year-old singer explained during his appearance on the show. "To find out she's going through the exact same thing at the same time ... All this has to be meant to happen."
When asked by Handler whether this was the happiest he'd ever been in his life, Shelton responded point blank, "No question about that. Absolutely no question."
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Stefani was a guest on the Late Show's "Carpool Karaoke" segment in May 2016, and got Julia Roberts and George Clooney singing "Hollaback Girl" when they hitched a ride with her and host James Corden. Check out the star-studded moment:
