"That's a no-brainer, right? I met my fiancée here," Blake Shelton said on The Voice's 10th anniversary special on Monday

Blake Shelton is recounting his love story with fiancée Gwen Stefani.

During Monday's episode of The Voice, the singing competition series marked its tenth anniversary with a special titled "Road to Lives — 10th Anniversary Edition," where the show's coaches looked back on the last 20 seasons.

Shelton, who's known for cracking jokes on the show, surprised fans when he got sentimental while reflecting on one of his "greatest" moments from the TV show: meeting Stefani.

"People ask me all the time, 'What's the greatest thing that has happened for you since you've been on The Voice?'" he recalled. "That's a no-brainer, right? I met my fiancée here. It's hard to resist Gwen Stefani. You know, here's this iconic rock star coming to be a coach on The Voice in a black minivan. That was cool to me."

"I love it when she's here. She brings a very complicated element of competition, for me in particular. But I love that. I love the challenge. Just knowing that she's there, and she has my back, is pretty cool," he continued.

Shelton and Stefani met on the set of The Voice in 2014 and dating for five years, announced their engagement in October. In The Voice clip, Shelton admitted he never expected the relationship to happen.

"If you had told me back in 1996 that Gwen Stefani was going to be my girlfriend, I would have laughed you out of the room," the country singer said. 

Gwen and Blake
Gwen Stefani and Blake Shelton's engagement
| Credit: Gwen Stefani and Blake Shelton

Shelton recently shared his first impression of the No Doubt frontwoman with PEOPLE, recounting, "She surprised everybody with a performance of 'Hollaback Girl,' and then they announced that she was going to be a coach."

"I remember enjoying her performance, and then after the show, we all took a group picture," he continued. "It was very much an industry-type meeting, and I told people, 'I met Gwen Stefani. That's crazy.' "

"People still can't understand how this possibly happened," Shelton said. "Like, 'How can she possibly want to be with this guy? It has to have been like a mix-up, right?'"

It was no mix-up as Shelton and Stefani are currently planning their wedding. Though they're still ironing out the details, they did get an offer from former Voice coach Miley Cyrus to be their wedding singer.

"@gwenstefani @blakeshelton I'll be your wedding singer!" Cyrus wrote on Twitter last month. "I promise to be on my best behavior. Or worst. whatever you want! It's your special day! Cheers to loving you both almost as much as you love each other!"