The No Doubt frontwoman reveals she was initially approached with a view to contributing one item to the project, but she had so many ideas, she offered to work on multiple products.

The result is her new Harajuku Lovers by Gwen Stefani Red Hot! line, from which a portion of profits will benefit the American Red Cross Home Fire safety prevention programme. The initiative aims to help reduce death and injury from home fires by 25 percent by 2020.

"I loved being able to create a whole super cute Harajuku Lovers collection that helps raise funds for a great cause," she tells People magazine. "In fact, I was originally asked to design just one product for this project to benefit the Red Cross, and I asked if I could put together the whole collection instead!"

The Red Hot! Collection, sold exclusively through PeopleShop, includes her five Harajuku Lovers fragrances with special metallic packaging, in addition to items like a recycled cotton Baggu tote, covered in emoji-like depictions of lipstick and pizza, and a box of nine high-end chocolates from Maggie Louise Confections, hand-selected by Gwen herself, and shaped like lips, stars, and even French fries.

The mother of three, who is dating country star Blake Shelton, has already started collecting items from the limited-edition range to give out as Christmas gifts.

"It also makes my holiday shopping much easier," she quips.

The capsule collection is Gwen's latest foray into the fashion world, after founding her first L.A.M.B. label in 2003. She has since expanded her empire to include GX footwear and a collaboration with snowboarding brand Burton, and she admits much of her closet space is taken up by her own designs.

"I'm really spoiled because instead of having to go shopping, I get to fill my closet with my designs," Gwen smiles. "I just got a giant box with the whole new L.A.M.B. for Burton collection the other day."

And as a style maven herself, the rocker likes to mix and match as she sees fit.

"I don't pay attention to trends," she says. "I just wear what I love."