SITTING next to each other in co-ordinated pink shirts, TV baking duo Mary Berry and Paul Hollywood are doing little to dispel their cosy image as the nation's favourite 'mother and son' pairing.

Not that they mind. "I'm surprised he doesn't say grandmother," quips Mary, 78, giving a wink with her heavy black eyelashes. "I have to keep my eye on him."

"Mary is like my mum," chips in 47-year-old Hollywood, whose steely blue eyes temporarily lift into a smile. "I feel like I'm with the family when I'm with Mary's family."

"And when we're with Mel and Sue, we are a family," chimes Berry. That 'family' is returning to BBC Two for the fourth series of cooking competition The Great British Bake Off, and after a tumultuous couple of months you get the impression that Hollywood is happy to be back in the baking fold.

It's not been an easy year for him. His marriage of 15 years broke down when he moved across the Atlantic to present the US version of Bake Off, The American Baking Competition, and there has been a rumoured romance with his US co-star Marcela Valladolid, 35.

It was hoped the show would launch his career Stateside, much like Gordon Ramsay managed to do, but it was unceremoniously axed after one series. The father-of-one has recently said he is "upset and sad" about his marriage split and feels like he wants to "disappear and hide".

But with a fresh series of The Great British Bake Off about to launch, and Berry by his side to protect him, it's clear disappearing isn't an option.

This year's competition will be different from the three previous series, in that 13 of the country's best amateur bakers will have their cake-baking, pastry, bread-making and patisserie skills tested to the limit over a 10-week period, instead of the usual 12.

Hosted by Mel Giedroyc and Sue Perkins, the show has been a huge hit with viewers. But as the years have gone by, it's clear that the participants have grown savvy.

"The contestants are getting wise. One of my favourite flavours is lime and I noticed a lot of lime this year," says Hollywood, who calls Berry "Bezza".

"They come up with a big smirk on their face going, 'Check that out' and I'm like, 'What's that?'. They say, 'Lime' and I'm like, 'Nice', and they know straight away they're onto a winner."

Berry has been writing cookery books since the Sixties, while Hollywood comes from a long line of family bakers. Even so, the pair admit they and the contestants have an uphill battle not to be outshone by witty host Perkins.

"Sue had that book, that really good one, How To Bake By Paul Hollywood," says the baker, who makes a few jokey references to his book throughout our interview.

"She was going through the book when we were going through all the technical challenges, and she'd come out covered in flour and say, 'Look at this!'

"She's a really good baker. She did me a Sally Lunn cake which is like a massive iced bun with loads of fruit in it and the icing didn't drip. It was really very good."

Although Hollywood and Berry claim that the standard among contestants is higher than ever, mistakes can happen in the big white tent.

"The first episode of this series was a bloodbath," says Hollywood, shaking his closely cropped salt-and-pepper head. "More than eight people cut themselves."

"The blue plasters were out," adds Berry. "There was a wonderful medic who was so busy. The bakers were nervous and it was cold so I think that's why they accidentally cut themselves."

The high street chain Zara will be pleased if Berry is cold, as last year sales of their floral bomber jacket shot through the roof after she wore it during filming.

"No one's more surprised than I am about that," she says with a mischievous smile.

"This year I've been quite brave, bold and cheerful with clothes. My daughter Annabel is terribly keen on getting her mum looking right and Lucy, my assistant of 23 years, says, 'Ooh you can't wear those', so I've taken advice from these people who care and it seems to have worked."

Though she's surprised by her style icon status, Berry is glad to fly a flag for older women.

"I hope I inspire people who are my age," she says. "You look round at people my age and they're in purple or mauve or black and white because that's what you do when you get old, but why not be more cheerful?

"But not too tight, not too short - Paul, what do you call them?" she asks, pointing to the tops of her arms. "Bingo wings?

"Well cover them up! It's being respectful of your age but having fun with it," she adds, smiling.

With all those tempting cakes in grabbing distance, Berry and Hollywood's waistlines could easily suffer but they insist they only eat a "small portion" of all the bakes. However, Hollywood admits to one politically incorrect weakness.

"I was in Waitrose and bought a sliced loaf, because I love bacon butties on a sliced loaf," he says. "The girl on the checkout was going 'beep, beep' scanning things through, and she stopped scanning, looked at the bread and said, 'What are you doing with that?' And I was like, 'Just put it in there!'"

Away from the screen, Berry and Hollywood make regular trips to each other's homes and often go to the pub, where Hollywood says Berry will "try to wrestle my wallet out of my hand" to buy the first round.

They're thrilled by the reception the series has had, and heartened by the number of people who've dusted off their scales, mixing bowls and pinnies again.

"I get tweets from international rugby players showing me their fairy cakes," says Hollywood.

Berry adds: "It's so rewarding because, instead of giving a bunch of flowers or box of chocolates, people are now giving cakes or bakes. Everywhere there are miniature bake-offs."

Hollywood says he's chuffed to be back in the Bake Off tent. "The first time I walked into the tent this year I had a massive smile on my face," he says. "It's like putting on a comfortable pair of slippers, and it probably feels the same watching it as it does doing it."

Extra time - Berry and Hollywood's baking tips

Berry: "A good cook has sharp knives."

Hollywood: "Digital scales are key."

Hollywood: "Baking is all about practice and practice makes perfect. My mum, bless her, can produce a great pie but the next day that pie may not be so good."

Berry: Good recipes are essential. Read them three times before attempting to make a dish.

Both: Don't be tempted to mix your flavours too much.

The Great British Bake Off starts on BBC Two tomorrow,Tuesday, August 20.

The Great British Bake Off Everyday - 100 Foolproof Recipes by Linda Collister is published by BBC Books, priced £20. Available now.