Gwen Stefani may have the coolest voice, the tightest abs, and the best moves since Mick, but she works hard at it – and we love her for that.

Deep in the tunnels of Madison Square Garden, the members of No Doubt are waiting to take the stage for their Grammy sound check. Ashanti’s run-through goes overtime – there are lots of children and a hydraulic mechanism involved – so No Doubt has some time to kill. The band is assembled in an anonymous room with bad lighting, one sofa, a makeup table, and some folding chairs. Drummer Adrian Young is engrossed in his iBook; guitarist Tom Dumont, in a knit cap pulled down low, and bassist Tony Kanal, behind dark glasses, lean back on the sofa; Gwen Stefani, in a cashmere halter top and combat trousers, is thinking of baby names that begin with G. The scene isn’t typically rock and roll. There’s no beer, no cigarettes, no bad words, only a couple of imitations of Michael Jackson shopping in Las Vegas. Suddenly Gwen leaps up to greet her parents, Patti and Dennis Stefani. She hugs her tall, burly father up around the neck, laughs when her mother says, “You look very California,” and then drags some chairs next to her.

Everything and nothing has changed since Stefani’s formative years in the Southern California city of Anaheim, where she was raised Catholic, where she picked out fabric so her mom could make her clothes, where she taught herself how to apply makeup with Mary Kay cosmetics, and spent her pocket money on rehearsal space for her band. “My parents were very strict,” Stefani says. “I had to wear white underwear until I finished high school. But they weren’t mean-strict. They were human, loving, and gave me morals, and I feel I’m very stable because of it.”

Stefani is a dichotomy, an accidental icon. She is a traditional girl with home-and-hearth values who leads three boys around the world in an arena-filling, genre-bending rock and roll band. She is the suburban American girl who now shares a place in the trandy Primrose Hill section of London with her British rock-star husband, Gavin Rossdale. That’s where she was a few weeks ago, eating ice cream in bed after Rossdale had cooked dinner, when the call came in: The Super Bowl honchoes wanted No Doubt for the halftime show. “Oh, shit,” she said to herself, as she finished off the ice cream, “now I have to start working out again.”

Evidently, Stefani’s notorious midsection, so well displayed by midriff-skimming tops, does not come naturally. Even though it’s her job, night after night, to jump around onstage until sweat pours off her, she does a lot of sit-ups in her hotel room. “I have to work really hard, unlike my husband,” Stefani says, laughing. “He eats chocolate every night before bed. Literally. If I did that, I’d weigh 400 pounds. But I get the sit-ups in, eat the right things. I don’t want people to think I just look the way I look.”

Stefani has to try hard at everything she does. She isn’t the product of a marketing department or a voice produced by a team of sound technicians. She became a singer in 1987 by happenstance (persuaded by her older brother, the band’s founding member), and then, during ten years of hard labor in a ska-influenced cult band, she earned a kind of goofy cool. Onstage, she makes cartoon-like, coquettish expressions while wearing Dr. Martens and tartan punker pants. In lyrics, she confesses her every-girl insecurities as if she were talking to her best friend. In videos, it looks like she’s having a ball. And she is. That’s the essence of her appeal. “I don’t have a lot to hide,” she says.

As an adolescent, Gwen – or Gwendolyn Renee, as she was christened – says she was chubby. “I think it started coming on in the sixth grade,” says Stefani, now 33 and sitting on an armchair in a private club in London. In person, she appears taller than she does on VH1; she’s lanky, long-limbed, and unbelievably fit. Stefani sits with her knees apart, like a boy, leaning one forearm on her thigh, yet she sips her coffee gently, pinching the cup’s china handle with silver-tipped fingers. She’s wearing a pristine white tank top with her demicup bra straps sticking out along with masculine tweed trousers. “My weight was a struggle for me, like all girls,” she says. “I don’t like to talk about it because it’s so boring. It’s something we all deal with. There is even more pressure for me, I think, because everyone comments on my body. I spend a lot of time thinking about it. And I admit that. But it’s just such a shame because there are many other things we could focus on.”

Since the success of Tragic Kingdom (released in 1995, it went on to sell 17 million copies), the popluar focus has been on Stefani. Never mind that she was one fifth of an ensemble. When the original singer died in 1987, Gwen moved to the front of the stage. Then her long-term relationship with bassist Tony Kanal ended, igniting her ire as well as her songwriting. She wrote “Don’t Speak,” and all of a sudden, she wasn’t just the cute girl with the high energy in No Doubt. Magazines wanted to take her picture and interview her, alone. Abruptly, the balance in the band – by all accounts, like a family of best friends – was thrown off.

“For nine years, we had been this cult band,” Stefani says. “We were equals. And suddenly there were all these outside people…” The outside people made the rest of the band resentful and confused. Their all-for-one-and-one-for-all days of touring the country in a beat-up van were over. “It was a real growing thing for us,” Stefani says. “Everybody got really mature about it and realized that, if you have a band, you’ve got to have a really good person up front.” And it doesn’t hurt if she’s blonde.

Hey Baby
Still waiting for sound check at the Grammy rehearsal, Stefani takes out her tiny red Nokia to call Rossdale. He has just flown to New York from London and is grumpy because the car service never showed up for him at the airport. Stefani’s assistant, Iona (who doubles as her yoga and Pilates instructor), says she booked a car and checked it twice. Stefani doesn’t bite her head off; in fact, she thinks it’s kind of funny. When No Doubt finally gets on stage, she has a good laugh at herself when she screws up – forgetting her microphone when she disappears to disrobe behind a giant steel vat. The boys smile, too.

The appeal of the funny, self-deprecating girl – untainted by the spoils of unimaginable success – has added up to millions of records sold, untold video requests, gigs opening for the Rolling Stones, and music festivals with U2. Award-winning duets with Moby and Eve began to demonstrate Stefani’s value independent of the band. That’s why she’s meeting with Hollywood film directors. That’s why LeSportsac commissioned her to design a line of bags. And that’s why the news of her own clothing line, L.A.M.B. (a secret acronym that she uses as a term of endearment), due in September, wasn’t dismissed with a collective eye roll as another episode of celebrity hubris.

At the 45th Annual Grammy Awards, the song “Hey Baby” wins No Doubt its first Grammy ever, for best pop performance by a duo or group with vocal. Onstage with the boys, Stefani says a few thank-yous, the excuses herself from the podium, clutching her small brass Victrola, before she chokes up in front of everyone. Stefani has had to try harder, which makes these milestones that much sweeter. It’s true she’s working on a solo album, not in spite of No Doubt, but because of No Doubt. “I prefer to think of it as a side project,” she asys. “It’s something I want to do before I have a baby.” She’ll be working with Dave Stewart of the Eurythmics, Dr. Dre, and her best friend, Tony Kanal, the guy who dumped her all those years ago. “I’m going to cry just thinking about it,” she says, raising the hand that wears a diamond-encrusted wedding ring with a big heart cut out in the middle. “I didn’t want to break up with Tony. But it was the best thing that ever happened to me. Because I found my gift, which I think is songwriting. It gave me a life, it gave me a personality, it gave me everything I have. He got the lifestyle he wanted, the whole wild band life. And I got to find Gavin, someone who really cares about me. And the one thing I feel blessed about, and both of us feel this way, is that our friendship remained. I mean, how rare is that?”