LONDON           -       Camila Cabello knows what she wants.

It’s October 2017, and the singer is walking the red carpet at Radio 1’s Teen Awards in London.

She stops to answer a few questions: What was it like working with Pharrell (“nerve-wracking”). Would you ever record a Spanish-language album (“definitely”). Then, as tradition dictates, we request a photo for the BBC’s social media accounts.

Cabello blinks, then asks: “Do you mind if I take a selfie?”

Next thing you know, she’s grabbed our phone and snapped four flawless portraits before being whisked away to her next interview.

It made an instant and lasting impression. Cabello had taken a throwaway moment and turned it to her advantage: The photo became our most-shared post from the awards, even after Gemma Collins fell through a trap door in the stage.

“Do you mind if I take a selfie?”

Fast forward to 2019, and Cabello is one of the biggest pop stars on the planet. She’s sold five million copies of her debut album, Camila; opened this year’s Grammy Awards with a Technicolor performance of her breakout hit Havana; and, alongside her boyfriend Shawn Mendes, released 2019’s most-streamed single, Señorita. Not bad for someone who, just seven years ago, was beset by crippling shyness.

“I was just kinda scared when I was little,” says the 22-year-old. “I was super-shy. Easily overwhelmed. I didn’t want people to look at me singing. I didn’t want people to ask me to sing.”

The story of her transformation is encapsulated in that Teen Awards moment. Cabello willed this version of herself into existence through hard work and self-belief, without surrendering her humanity. “I see her as an absolute force of nature,” says the star’s manager, Roger Gold. “She worked on herself so much and so hard - as a singer, and a dancer and a songwriter. She knew she could make herself excellent in every category, and she knew what she had to do.

“That vision and that desire to get there... what it makes me think of is Madonna.” Born in Havana to a Cuban mother and Mexican father, she moved between the two countries until she was six, when her mother announced they were going on a trip to Disney World. Instead, they travelled from Cojímar to Mexico, where they caught a bus to an immigration centre on the US border.

After crossing into Texas, they made a 36-hour journey to Miami, arriving with just $300 and a backpack of possessions, including Cabello’s Winnie the Pooh journal and her favourite doll.

For 18 months, they scraped by on the modest salary her mother, who’d been an architect in Cuba, made in the footwear concession of a department store.

Eventually, her father swam the Rio Grande to join his family, earning money by washing cars “in the blistering Miami heat”, and saving up until the family had enough money to start a construction company. Looking back, Cabello says she was blissfully unaware of her parents’ struggle. “I don’t think you realise that stuff as a kid,” she says. “You’re either happy or you’re not. “I remember being at my mom’s job during the summer, under her desk playing house, and to me that was fun. When you’re a kid all you really need is your imagination.”

For a long time, her imagination was where Cabello lived. She’d rush home from school and devour the Disney Channel. “The Cheetah Girls, Hannah Montana, High School Musical: That was the golden era of my childhood, because all my friends were obsessed. We were just obsessed with it.”

Online, she’d come up with silly nicknames to make her schoolmates laugh. “One year on Facebook, I was Billy Bob Billabong Cabello,” she giggles. “I don’t know why, I just thought that was funny.”

When she hit her teens, her musical horizons widened to include Taylor Swift, Ed Sheeran and, especially, John Mayer’s FreeFallin’, which she played on repeat for an entire year.

“I would love to go on YouTube and sing karaoke and watch One Direction videos,” she recalls. “I would just escape into music.”