Forget expensive creams or complicated skin care regimens — Gwen Stefani says her beauty secret is how happy she's been since finding love with her country star fiancé, Blake Shelton.

"Blake is the greatest guy," the pop star gushes in a new interview with Australian publication Herald Sun.

"I look back over the past few years and look at pictures of when I first started kissing Blake, and I look the best I've ever looked in my life in those photos," she says. "Love must look good on me. I feel like that does show through — it really does."

Stefani, 51, has been in the public eye for more than two-and-a-half decades: First as frontwoman of ska-pop band No Doubt, and then as a successful solo artist. During that time, her various looks and styles have been among the most iconic of any pop artist. She's been known as a '90s fashion icon who wore ab-revealing crop tops, blue hair tied up in space buns and elaborate facial jewelry; later on, Shelton tipped his hat to her signature "Revlon red" lipstick in the lyrics of his 2018 single, "Turnin' Me On."

Stefani admits that she's faced pressure to age gracefully over the years.

"It's really hard for everyone to age and have to face life," she acknowledges. "Especially for females and people who have been in the spotlight, it can be daunting, but you tackle it by just trying to be the most beautiful version of yourself inside and out."

For the pop star, that means basking in the happiness of family life with Shelton and her kids as she focuses on new music. Next up, the happy couple are looking towards planning their wedding. Shelton recently shared that while the details are still being ironed out due to the COVID-19 pandemic, they're hoping to plan the ceremony for the summer of 2021.

"People talk about my aging as a compliment, I guess. I'm kind of obsessed with how I'm aging, too," Stefani admits.

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