At a concert in Oklahoma on Friday, the country singer plated a kiss on his girlfriend when she joined him on stage during the show, and adorably embarrassed her a bit when he started dishing on the early days of their romance.
Some of those in attendance at the private concert shared the cute moment to social media, and captured the No Doubt singer's bashful smile as Shelton jokingly teased her about the start of their flirtation.
"We were starting to hang out together and mess around," Shelton, 41, recalled as the audience cheered in support and Stefani, who had rested her head on his shoulder, looked up at him mock-surprised at his candidness.
The intimate performance was held for around 150 fans in Tishomingo to promote the opening of Shelton's first restaurant, Ole Red, where the sweet couple was also spotted smiling wide as they walked hand-in-hand.
Additionally, the event raised money for local charity Johnston County Reaching Out.
ET's Sophie Schillaci caught up with Shelton before the concert at the opening of his restaurant, where he opened up about the news that his close friend, Luke Bryan, has signed on as a judge on the upcoming American Idol reboot.
"I think people are going to realize just how dumb he really is when they see him on national television, in an environment where there's no script," Shelton joked. "But you're also gonna see what a great, great dude that guy is… I love Luke like a brother, I really do, but he's just dumb."
Tune into to Entertainment Tonight on Monday for more from ET's sit-down with the country crooner and Voice coach. Check here for local listings.