Blake Shelton was already a household name for many people when he signed on for the first season of The Voice in 2011, but not for Gwen Stefani. She says she had no idea the country star existed!

"I didn't even know he existed before the show," Stefani admits to Andy Cohen on his SiriusXM Radio Andy show. "I didn't even know that he was a human being on this planet."

Shelton's debut country single, "Austin," came out ten years before he went to Hollywood to coach the NBC reality singing competition. Stefani, of course, is the frontwoman of the pop-rock-ska band No Doubt, and given their different genres, it's not shocking that their paths never crossed.

They've been dating since 2015, after meeting on the show, and Stefani admits it took awhile to get used to their differences.. "It’s crazy. I mean, now it’s normal," she says. "I’ve accepted that he’s a true hillbilly and all those things."

Blake Shelton Is a "Good Dad" to Gwen's Three Boys

In the same interview, Stefani also talks about the song she and her boyfriend of four years cut together, "Go Ahead and Break My Heart."

"I remember he came over, we were going to practice it for the first time. I mean we had hardly barely even hung out. I think I sweated through my entire clothes trying to sing while he played the guitar," she says. "We wrote this song and we weren’t even in the same song when we wrote it. He sent me a verse and then I sent him back on my phone the answer to it in the song. That was definitely exciting. I guess more exciting than nerves."

Now that she knows him well, Stefani has grown to love Shelton's brand of music, too — she says her favorite song is "Mine Would Be You." along with a song he wrote specifically for her.

Stefani also talked about her favorite Blake Shelton songs, and revealed "Mine Would Be You" is among them, along with a song that Shelton wrote about her.

The Voice airs Mondays and Tuesdays on NBC at 8PM ET, with both Stefani and Shelton in the coaching chairs.

Shelton tickets are still available to all of his shows still slated for 2019.

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