A Hampstead children’s charity offered its supporters a unique culinary experience as celebrity chef Yotam Ottolenghi gave a rare live cooking demonstration.

Launching its first official fundraiser since starting in January, charity Spread a Smile ran the demonstration and Q&A with one of London’s most popular chefs in Hampstead last Thursday.

News that the Israeli-born chef, owner of four restaurants and author of six best-selling recipe books, was the star guest, spread like wildfire and organisers said the event could have sold out three times.

When Mr Ottolenghi heard the stories of the sick children helped by Spread a Smile, he found it hard to turn down the opportunity.

“I receive so many charity requests but this one stood out,” he said. “The work they do and all the stories I’ve heard today about the kids they help – it’s been overwhelming. When you find a cause that is really worth people’s support you’re just honoured to be able to help where you can.

“It was great being able to give people a few cooking tips too – serving someone a delicious meal really can be the quickest way to put a smile on someone’s face.”

That’s exactly what Hampstead residents Josephine Segal and Vanessa Crocker intended when they set up Spread a Smile.

Following the illness of Josephine’s nine-year-old nephew, which saw him hospitalised for months at Great Ormond Street last year, she and the boy’s mother Caroline Maurice saw first-hand the misery that can result from an extended stay in hospital.

As the child was hooked up to several machines, the pair tried to find ways to break up the long days as he grew increasingly withdrawn.

In the end they decided to arrange for a magician to visit, on the off-chance he would cheer him up, and the effect was instant.

From that moment, Josephine realised this was something that all sick children could benefit from.

With a collection of top entertainers – including Magic Circle magicians, storytelling fairies, professional singers and animal face painters – the charity she and Vanessa established has helped bring children a more “Patch Adams” style of healthcare to Great Ormond Street.

Their work has been welcomed by doctors at the hospital.

Dr Ilana Karno, a paediatrician, said: “There’s a growing body of evidence emerging showing the link between high levels of stress and depressed immunity which can cause slower recovery, so doctors welcome anything which can reverse this.”

Plans are in place to expand the charity’s work in the teenage cancer ward at University College London Hospital.

For more information on the charity, visit www.spreadasmileuk.com.