Last year’s Great British Bake Off had pretty much everything you could wish for in a television baking contest. Brilliant bakers, jaw-dropping creations, nerve-jangling evictions… and a winner who almost quit in the semi-final. As a fresh baking dozen enter the famous tent for this year’s show, fans must all be wondering the same thing – just how do you follow that?

‘Well, I have to say, I think that every single year,’ admits judge Dame Prue Leith. ‘I think, “It’s got to start getting worse, it can’t go on getting better.” But it does.’

Presenter Alison Hammond agrees. ‘It’s unbelievable,’ she says. ‘They’re really exciting bakers. There’s something magical about that tent… it changes people. Everyone goes on a journey. As you might expect, there are a few failures. But many of those failures are me having accidents in the tent,’ she adds, laughing. ‘It’s Bake Off at its best, though. People are going to be blown away.’

The Class of 2025, whose efforts are assessed once again by Prue and Paul Hollywood, range in age from 23 to 59. Among those hoping to emulate reigning champ Georgie Grasso (the first Welsh winner) are an advertising consultant, a medical student and an office assistant. ‘And we had a lot of designers and engineers too,’ says Prue. ‘It shows in their baking. They’re much better at construction. We also have artistic people like hairdressers or stylists.’

There are two new themes this year. Back To School Week sees Alison, who co-hosts the show with comedian Noel Fielding, channel her inner teacher with delight. ‘I was ringing bells and telling everyone off,’ she says. Meringue Week, meanwhile, is bound to give fans flashbacks to perhaps the show’s biggest controversy: Bin-gate, when Diana Beard was accused of sabotage by viewers after removing Iain Watters’ Baked Alaska from the freezer in 2014. He threw his thawing dessert in the bin, came bottom and left the tent. The 40 seconds it was out on the bench wouldn’t have defrosted the ice cream, but that didn’t stop a furore that was even discussed on Newsnight.

Ice cream and meringue combine once again this year for a Vacherin Glacé (or French Ice Cream Cake) showstopper. Did this summer’s heatwaves cause similar meltdowns? ‘There are one or two that aren’t frozen,’ says Prue. ‘They’re more like trifle, a bit squashy, but they manage quite well.’

‘There is another Bin-gate this year, though,’ teases Alison. ‘I’m not going to elaborate, but you’re going to love that moment. We’ve given you a big secret there…’

The contest kicks off as usual with Cake Week. The signature challenge is a Swiss roll with an inlaid design. Next, the bakers tackle the technical task – fondant fancies – without a recipe. And the showstopper? The bakers must transport the judges around the world with cakes inspired by their favourite landscapes.

With her third series observing the judging and tasting the bakes now under her belt, Alison feels like an old pro. ‘You can see how Paul prods the cake,’ she says. ‘If he doesn’t get a bit of a spring back, if it doesn’t crumble right, you can see what he’s going to say. You learn quite a bit.’

Resisting temptation when the quality is so high can’t be easy. Alison has lost more than 11 stone in recent years, prompted by the discovery that she was pre-diabetic – a situation she has reversed with healthier food choices and workouts. This year she has been admirably disciplined, only gaining 2kg (4½lb) during filming. Does she restrict herself to showstoppers only? Or use a teaspoon?

‘I eat a bit of Paul and Prue’s after they’ve finished judging,’ she says. ‘I only try the ones that got a handshake from Paul or ones that won. If the judges aren’t impressed, I’m not trying it.’

And Prue’s secret to staying trim? ‘I don’t eat breakfast or lunch,’ she admits. ‘My theory is that leaves me enough spare calories for a couple of glasses of wine at supper. My diet during Bake Off days is basically cake and red wine. What’s wrong with that?’ Nothing at all, according to Alison. ‘Prue’s in her 80s. She’s allowed!’ she says.

With the show reaching its 150th episode mid-series, it’s a chance to toast the national institution. It’s hard to imagine a time without Bake Off buoying our spirits as we head into the darker days of autumn. ‘Once it had passed its 50th episode, you knew it would go until it’s 500th,’ says Prue. ‘It seems part of life now, doesn’t it?’

Alison nods. ‘Bake Off’s so simple. It’s cake, beautiful bakers with a story and that’s it. They don’t even win any money. They come on the show because of their love of baking.’ And they’re mates, adds Prue. ‘They all want to win, but they don’t want anyone to lose.’

Prue and Alison became fast friends themselves when the This Morning host joined the show in 2023. They’re both adventurous and free-spirited Aquarians. ‘Probably the reason we get on,’ says Alison. ‘It’s the sort of relationship where I’ll take the mickey out of Prue, but if anyone puts her down I’m going to fight them like a lioness. I’ll defend her to the death. Prue’s incredible. Her work ethic’s on another level. She never complains. And if I’m as fit as she is in my 80s, I’m going to be very happy.’

Prue loves her pal’s playful exuberance. ‘It’s very hard not to be merry around Alison. She’s always happy, so she lifts the tent. Even grumpy old Paul is happy around her.’

Mr Hollywood calls Prue ‘solar-charged’ because he never sees her battery deplete. Now 85, she’s in good health, but says, ‘I’m beginning to get arthritis. My thumbs, if I’m unscrewing a jar I struggle, but you know, something’s got to give in.’

What gives her all that energy? Vitamins? Meditation? Sunshine? ‘I don’t do any of that nonsense,’ Prue laughs. ‘I’m too impatient to be bothered with anything that requires me to chill out. I’ve tried many times to meditate. Within five seconds I’m bored. I can’t get my head around mindfulness.’

What does she think of Ozempic and other weight-loss drugs? If her dinner guests pushed food around their plates, would she feel offended? ‘I’d be worried about them, but I wouldn’t be offended if they didn’t eat,’ she says. ‘People worry needlessly about a lot of things. Yes, it’s important to have a healthy diet, but I don’t think you need to be neurotic.’

Despite her attitude, Prue said earlier this year that she didn’t know if this series of Bake Off might be her last. Is that on her mind now filming has finished? ‘Well, it is,’ she admits. ‘It often is because I’ve got to stop some time. But I love Bake Off, so not yet. I love it so much there’s a danger I’ll overstay my welcome.’

‘Never!’ declares Alison. ‘You could still be here at 101. I don’t know why you’d retire. If she left Bake Off she wouldn’t stop working, so she might as well stay.’

Indeed. Prue’s the living embodiment of it never being too late to try something new. Aside from judging Bake Off and its US counterpart, The Great American Baking Show, in recent years she’s toured a one-woman show on both sides of the pond and made two series of Prue Leith’s Cotswold Kitchen on ITV with her husband of nine years, retired fashion designer John Playfair. She’s also found time to write two cookbooks, travel to Australia and along the Silk Road, and appear as Pegasus, the mythological winged stallion, on The Masked Singer after months of singing lessons.

She also campaigns heavily for Dignity In Dying, having witnessed her brother David’s agonising death from bone cancer. In June, MPs approved the assisted dying bill by 314 votes to 291, and now it will proceed to the House of Lords. How does she feel about things as they stand? ‘Well, we’re closer to getting a law passed and we will have it passed,’ she says, ‘but there are arguments on both sides. People who object are worried about safeguards. They’re worrying unnecessarily. If you look at jurisdictions where assisted dying’s legal, there have never been families saying, “My parents were pushed by the hospital into accepting death.”

‘None of the countries that have assisted dying have repealed the law or wanted to change it. And when you poll citizens, they’re happy it’s there. It’s the comfort of knowing you have the choice. Where it’s legal and people have signed up and asked for the medication, two-thirds never take it as they have a perfectly OK death anyway.’

Prue pays tribute to her fellow Dame, Esther Rantzen, another vocal supporter. ‘I don’t know her well but she’s been amazing. She really is very ill now. She’s always been full of energy. She’s always been a campaigner. It’s typical of her that she’s spending her last months campaigning for something that probably won’t happen in time for her.’

Alison’s more in demand than ever too. Aside from Bake Off and This Morning, she took over primetime favourite For The Love Of Dogs after Paul O’Grady’s death. She’s co-authored her first novel, Bombshell, and got her own chat show, Alison Hammond’s Big Weekend. And her travelogue Florida Unpacked with her 20-year-old son Aidan was compulsive viewing.

Surely more destinations beckon? ‘We might do another next year. We talked about Europe.’ They’d be perfect for Celebrity Race Across The World, too. ‘Aidan said he’d love to do that, but I don’t think I could cope,’ Alison admits. ‘That’s a hard show. You’ve no money, you don’t know the language, you’ve gotta find your way around. It’s too scary.’

She isn’t worried about Aidan being called a nepo baby. ‘People are going to see things for what they are,’ she says. ‘You’re always gonna help your child. I know carpenters who’ve trained their sons to be carpenters. It’s a normal thing to do. He’s been in the environment, so he’ll probably fall into the family business.’

Before finding fame on Big Brother, Alison was a child actor and appeared in TV shows such as Palace Hill and Chalkface. ‘Mum used to do work as an extra and I followed her around, so I fell into it,’ she says. ‘So I’m a nepo baby as well, if that’s the case, but you’re going to fail if you’re no good. Ultimately, Aidan’s going to have to pave his own path. I can open a few doors, but if he’s no good, those doors are going to be closed.’

She doesn’t like to talk about her private life, but Alison has found happiness off-screen with her partner, Russian masseur and model David Putman, who is 22 years her junior. In February she celebrated her 50th birthday. How does that feel? ‘I feel so blessed to have got to this age,’ she says. ‘A lot of people don’t. I’m happy to be still breathing every day. I went to New York with my boyfriend and we had a lovely time. We went sightseeing and it was so romantic.’

Prue raises an eyebrow. ‘It’s funny Alison thinks it’s amazing to get to 50,’ she says. ‘That’s a child’s age. I love your phrase… you’re lucky to still be alive. My husband says, “Let’s just try to stay the right side of the grass.” I’m writing a book called Being Old… Or Staying The Right Side Of The Grass.’

That could be Alison’s bible for the next 35 years. ‘Exactly!’ Alison says. ‘It’s lovely to have Prue because you can see what’s possible.’

The Great British Bake Off returns to Channel 4 next month.