When Nelly Furtado stormed the charts as a 21-year-old in 2000, with the inescapable single I’m Like a Bird, the Portuguese-Canadian newcomer discovered that she had some escaping to do herself. A jaunty, infectious radio song, it nailed her in the public’s imagination as a bouncy, permagrinning pop popsicle, all hoop earrings, hipster jeans and trilled choruses. Whoa, Nelly!, the album from which the song came, sold almost 7m copies. Nice work if you can get it.

Except that Furtado didn’t quite see it that way. Lacking a killer single, her 2003 follow-up, Folklore, sold a relatively meagre 2m. And the singer, as if determined to take career self-sabotage to its furthest extreme, had a baby.

She’s been alternately fleeing and warily embracing the success I’m Like a Bird set in motion ever since. Part of the problem has been that the focus on the poppier end of her recorded output meant that the real eccentricity and eclecticism in her work (hip-hop, Portuguese fado, breakbeat, folk) was overlooked. Folklore contained church organs, a choir and a guest appearance by the Brazilian Tropicalian legend Caetano Veloso. “I think I’ve spent my whole career trying to explain who Caetano Veloso is,” Furtado laughs. “Or going, ‘I’m not really that weird, wait. There’s a point here.’”

Her current rapprochement with the mainstream involves a startling new set of songs produced by the uber-hip-hop studio wizard Timbaland (aka Tim Mosley, Missy Elliott’s key collaborator). Its lead single in Europe, Maneater, is a sensational return to radio accessibility, albeit one laced with enough sonic weirdness to keep the purists happy. The first track the pair worked on in Miami, it was also very nearly the last, as a fire broke out in the control room. “The jam was so intense,” says Furtado, “and suddenly, we were, like (she sniffs), ‘Did you smell that?’ And these flames shot out of the speaker. I like symbolism. Isn’t that neat?” Acknowledging that the story seems too good to be true, and designed to whip up a storm of excitable pre-release publicity — Furtado/Timbaland Collabo So Hot It Torches the Studio — she adds, drily: “It does sound like an urban myth.” Meanwhile, Promiscuous, a lascivious Furtado and Mosley two-hander that will be the next single here, is laying waste to north American airwaves.

On a restaurant patio in Toronto (where Furtado now lives), I overhear four women — three designer-label mavens and one slightly out-of-place indie chick — discussing the track. “It’s, like, so hot,” purrs one of the mavens. “It sucks,” counters Indie. Which is, arguably, Furtado’s quandary in a nutshell.

Before she recorded Folklore, she asked herself a question you suspect she still hasn’t quite found the answer to. “I was living in this rented house in LA,” she recalls. “I had just finished touring for three straight years, and obviously I hadn’t really had any personal development in that time. And one day I saw this picture of myself in a magazine, with the prettiest gown on. And I just went, ‘What does it all mean?’ When I was a teenager, I wanted to be (the feminist punk-folk singer) Ani DiFranco. I never wanted to be part of corporate music.”

Furtado’s daughter, Nevis, was born three years ago. The singer and Nevis’s father, the rapper Lil’ Jazz, have since split up. It was only mother and daughter, then, who travelled down to the sun and sand of Miami last year to make what Furtado calls a record with “an ‘I’m single’ rush” to it. Days were spent doing family things. Nights meant the studio.

“Tim would show up in his $300,000 car,” says Furtado.

“He wouldn’t start till midnight. When I was 14, living in suburban British Columbia, I absolutely idolised every hip-hop and R&B star. I was obsessed. And there I was, at the Hit Factory in Miami, actually working with real rappers.”

That teenage passion manifested itself to a limited extent on Whoa, Nelly!, but it would be wrong to say that it dominates proceedings on her new album, Loose. After all, in the eccentric and eclectic stakes, Furtado, who studied the ukelele and spent her youth playing trombone in a marching band, was always going to meet her match in Timbaland. She last worked with him on a remix of Elliott’s Get Ur Freak On, and has described him arriving at the studio for the Loose sessions “with this huge duffle bag, carrying all these CDs of mostly crazy world music”.

Yakking about shared likes and dislikes, the two musicians discovered a mutual love for the 1980s; so much so that they soon started referring to one another as Annie (Lennox) and Dave (Stewart).

“We were talking about bands like Eurythmics and Blondie,” she says, “and the theatrics of 1980s music. A lot of people have put 1980s things in their music, but it’s a little kitschy. But we were like, there was something cool about how pulsating the beats were, and how rich the synthesizer was. And current indie rock is sexy, it’s rhythmic again. It makes you want to move your body, like when you’re dancing in your underwear by yourself in your room.

And it’s not like, ‘Ooh, rap and rock? Well, here’s a rap-rock song.’ It’s tangible.”