It’s an unseasonably grey summer afternoon in London, where Salma Hayek is ameliorating her reputation as something of a task-mistress.

“It was Alfred Molina who said that if I was a man and I was white, I would be bigger than Harvey Weinstein,” she laughs. “It was Harvey Weinstein who called me a ball-breaker.”

High praise from Caesar, indeed. It’s not the size of the package. Classically and girlishly proportioned, cheery, chatty and standing at a petite 5 ft 2, Salma Hayek is a habitual dasher of expectations.

Born in Coatzacoalcos, Mexico to an opera singer and an oil executive, Hayek enjoyed a cultured and comfortable childhood. In defiance of an early double diagnosis of dyslexia and ADHD, she read international relations at Universidad Iberoamericana before finding work as the star of Teresa, a hit 1989 telenovela. Screen acting, she says, was just always a good fit.

“My mother encouraged me to sing,” recalls Hayek (49). “She seems to think I have a voice. The big difference between her and I is – and it’s very strange – I have stage fright. She feels at home performing in front of crowds. She happy. There’s no anxiety. But there’s always anxiety for me in front of an audience. I don’t experience that on a film or television set. Because being an actor you are becoming someone else. It takes the pressure away.”

Hayek was one of her country’s biggest soap opera stars by the age of 22. Yet, when the hotly tipped young Mexican arrived in Hollywood in 1991, studio and casting folks repeatedly and indelicately explained that nobody would hire her – because “people don’t like to be reminded of their maids”. A lesser mortal might have taken it to heart.

“I wasn’t insulted,” she says. “It was more like I was in awe of the level of ignorance and confusion. I didn’t even take it personally. I had clarity about myself. It just surprised me that people who were in positions of power could be so limited in their vision. I knew they were wrong. And I had to show them that they were ignorant.”

Happily, she soon fell in with the young Miramax gunslingers. In 1995, director Robert Rodriguez cast Hayek opposite Antonio Banderas in Desperado. Something clicked: she and Rodriguez have worked together on Four Rooms, From Dusk Till Dawn, The Faculty, Spy Kids 3D and Once Upon a Time in Mexico.

Away from this Tex-Mex oeuvre, Hayek broke the colour barrier and built up credentials as a credible romantic heroine, starring with Matthew Perry in Fools Rush In and Russell Crowe in Breaking Up (both 1997).

She was also embraced as a good sport, a funny woman who could rise above the occasional flop, such as Kevin Smith's Dogma (1999) in which Hayek plays a muse-turned-stripper, or Barry Sonnenfeld's Wild Wild West (1999), in which she plays a scientist's wife posing as a prostitute.

Sexy girl parts

Speaking at a panel at Cannes last month, Hayek said that, during this period, she’d take “the maid or sexy girl parts”, but then seek to expand her role as soon as she arrived on set.

“When I first started, everything was a given,” she tells me. “There wasn’t even the possibility to question the system. These are the rules. These are the only parts you can play. This is how things are and this is how they should be, and that was that.”

Getting her foot in the door was soon not enough for Hayek. By the turn of the millennium, she moved into production with The Velocity of Gary, a gritty New York drama concerning a hustler with Aids, and his makeshift bohemian family. In 1998 she founded Ventanarosa Productions, with the intent of creating significant roles for Latin women.

“I don’t enjoy producing,” she says. “But I recognise I’m good at it. It’s a way of combating certain limitations. I can do what I want. I can be a participant.”

She spent more than eight years putting together Frida. Hayek's 2002 biopic of Mexican artist Frida Kahlo required her to convince a long list of stars (including Ashley Judd, Geoffrey Rush and Edward Norton) to work for scale. She also secured complete cooperation from Dolores Olmedo Patino, Diego Rivera's former lover, and the administrator to the rights of Kahlo and Rivera's art. She even managed to sweet talk Harvey Weinstein and Miramax into buying the film when the production stalled.

It turned out to be a good move: Frida made $56.3 million back from a budget of $12 million, and saw Hayek notch up best actress nominations from the Oscars, Baftas, Screen Actors Guild and Golden Globes.

"I do like being behind the scenes," Hayek says. But she wasn't done. In 2003, she won an Emmy with her directorial debut, The Maldonado Miracle, and the following year adapted a Colombian telenovela called Yo Soy Betty, la Fea for US television.

Wit and humanity

People thought she was mad as a balloon. But Ugly Betty, as the project became known, had a sizeable and international cultural impact, ran from 2006 to 2010, and won two Golden Globes, a Screen Actors Guild Award and a Peabody – "for demonstrating that wit and humanity never go out of style".

"When we made Ugly Betty, I couldn't get it on the air," says Hayek, who executive-produced the show and won an additional Emmy for her guest-starring role as duplicitous magazine editor.

“First of all, we were breaking a lot of television rules. There had never been a one-hour comedy before, with a lead female character who was not an extraordinary beauty. And on top of that, it was Mexican.

“How I finally got it on the air was by doing research and tapping into the power of the Latina consumer in the US. I got a commitment from the advertisers to advertise during the show. And I then went back to the network that had rejected us. Nobody had done it like that before. It worked.”

Another unexpected twist: having established herself, Hayek has been rather quiet of late. Because of family.

In early 2007, she announced her engagement to French billionaire François-Henri Pinault, the chief executive of Kering, which owns Gucci, Saint Laurent, Stella McCartney and Alexander McQueen. Hayek gave birth to a daughter, Valentina, in September of that year. She married Pinault in 2009 on the condition that she wouldn’t be arm- candy or a society wife.

“He liked that,” she laughs. “But when my daughter was born, I really didn’t want to work anymore. I wanted to retire completely. And my husband was brilliant. He said you have to work. ‘This is the hormones talking; if you completely disappear for years, you’ll want it back.’

“He was very pushy on the subject. But he said something really beautiful. He said: ‘The world is completely unaware of your capacity. I can’t keep you away from the world. They have to find out.’”

She laughs: “It was beautiful but, at the same time, it put the pressure on.”

The pair were initially more inclined to bond over their mutual love of football than fashion. But Hayek has slowly come around.

“Fashion was never a passion of mine,” she says. “Through him I’ve learned to appreciate it a little more. It’s a difficult business. But it can be a beautiful way of expressing yourself. My daughter never wants to wear what I want her to wear. And I don’t fight her. She’s figuring out how to express herself. And that’s wonderful. As long as it’s weather appropriate.”

Dark fairytale

And now she's back. Hayek didn't hesitate when Italian director Matteo Garrone asked her to play a queen struggling to conceive a child in Tale of Tales ( Il Racconto dei Racconti), a portmanteau of dark fairytales in the adult-friendly style of Angela Carter.

It’s not just that she came late to motherhood.

“I did identify with that. But every woman, one way or another, experiences the anxiety of motherhood. For some women the concern is whether they want motherhood or not. Or can I afford to have a child? Or am I going to be able to have a baby or not? Am I going to find someone to have one with? There is so much anxiety around motherhood.”

Tale of Tales marks a radical departure for Garrone, whose best-known film, the crime epic Gomorrah, could hardly have less to do with fantasy.

“It was a surprise,” says Hayek. “When we saw it for the first time at Cannes, Toby Jones was sitting next to me and the minute it was over he said: ‘Wow. Now I get it’. And I felt the same way. That’s not because I’m in it. I love this film. I would have felt happy just to see it.”