When you've sold more than 48 million books worldwide, and hosted multiple successful TV shows, not to mention running a restaurant empire, you might be forgiven for not taking on any more projects. Not so for Jamie Oliver.

Britain's bestselling non-fiction writer of all time has only gone and written a children’s book. But he never really meant to publish it, he told Kathryn Thomas:

"I didn’t intend to do what I’ve done, which is publish this book. Really and truly, I had put the kids to bed, I would read to them and, as they’re growing up – this is actually with Petal and Buddy – I'm dyslexic, so I’ve always, like, words have always been my enemy and they’ve always freaked me out a bit."

The conversation mentions dyslexia a lot and it’s pretty clear from the outset that Jamie is passionate about kids and adults getting the help with their neurodiverse issues that he didn’t get as a child:

"I didn’t read my first book until I was 35. And primarily that’s because I fall asleep after ten pages and I can’t focus and the words do weird things and when you’re like that, your kids get better than you at reading quite quick. So my kids were like, 'Don’t read! Can you read us a story from your head?’ So that’s what I would then start doing."

At first, Jamie didn’t entirely focus on the task at hand, as his attention tended to drift elsewhere:

"It wasn’t whimsical and romantic – I was dreaming of them being asleep and having a gin and tonic."

So Jamie started randomly telling stories to Petal and Buddy at bedtime, but then he decided to record them, so he could maintain some kind of continuous narrative and characters. He ended up with what he describes as "a whole bunch of stories".

"Over lockdown, because I’m so frightened of words – and I’m not dramatizing that, I think anyone that’s listening that has the same relationship with words and focus and getting on – I've never had a shortage of ideas and fantasy and I love stories and I love being told stories, but the idea of writing is a nightmare. So I had it on Dictaphone, I had it transcribed and then I started creating like little stickies and building up a room, a physical room of characters and views and I ended up writing this book."

Jamie and his illustrator Mónica Armiño and the publishers went to great lengths to make the book as dyslexic-friendly as possible:

"It’s the most dyslexic-friendly font and there’s lots of like personal nuance in there, like, you know, the chapters will only ever start on the right-hand side, you know, really like the way that I designed the pages, and the words and you’ll see some of the expressive words getting into bigger fonts and become more sort of visual. So these are all things that helped me as a kid, which obviously I can do in my own book because it’s my book."

Kathryn points out that, although the book is for kids, there’s a lot of great nostalgia in it for adults. Jamie tells her that was – naturally – deliberate:

"I wanted to write this book for me as well as the kids. You know, really, like, in code, the book is about the wonder of nature and growing and the importance of fantasy. And then if you’ve dived into the characters, if you’re not a conventional learner or can’t do things conventionally, it’s overcoming those challenges in different, creative ways."

The book spans timelines, allowing for that nostalgia hit for parents reading to their children, along with contemporary settings and a brush with magic:

"It’s set in the current time now, with the parent putting the two kids to bed, just as I did when I created the book, it’s set in the 80s, in a little village and there’s a wood that some, like, dark secrets and they stumble across another world by pure luck."

That’s the 80s, the present and magic. Plenty of attention-grabbing boxes ticked for eager kids and gin and tonic-seeking parents. And, naturally, given who wrote it, food gets plenty of page time too:

"It’s not hard-selling food, it’s not pushing food, but important stuff happens over dinner tables and lunchtimes and breakfasts. I mean, as you know, like, kitchens are the most important part of the home, no matter what."

Jamie brings the conversation back to dyslexia and tells Kathryn that all roads lead to education:

"Education has such a long way to go with neurodiversity. As someone that left school running, as someone that hated the written word, you know, it’s taken actually this kids’ book to finally brush the last set of chips off my shoulder. It’s the most important book I’ve ever published, to me emotionally."

Coming from Britain’s all-time best-selling non-fiction author, that is quite a statement and it goes to underscore Jamie’s genuine interest in supporting neurodiversity – and bedtime reading.

You can hear Kathryn’s full conversation with Jamie by going here.

Billy and the Giant Adventure by Jamie Oliver is published by Puffin.