$36 million in a year and thousands of jobs lost: How it all went wrong for Jamie Oliver.

For 20 years, Jamie Oliver has been one of the most recognisable chefs in the world. But while his TV shows have always been casual and fun, his behind-the-scenes business ventures have been far more tumultuous.

We first saw Oliver in 1999 when the BBC debuted his TV show The Naked Chef, and since then he’s been a permanent fixture on our screens and in our kitchens.

The 44-year-old went on to star in several cooking shows including Jamie’s Kitchen and Jamie’s 15 Minute Meals, and is now broadcast worldwide across 220 channels.

Here is Jamie Oliver talking to Sunday Night about his financial troubles last year. Post continues after video.

In 1997, father-of-five Oliver worked as a sous-chef at London’s Michelin Star winning Italian restaurant The River Cafe.

It was here that he got his break, when a colleague called in sick and Oliver was required to work the day a documentary about the restaurant was filming.

After it aired, Oliver was called by five different TV production companies. In April 1999, The Naked Chef premiered.

Oliver has 20 books printed in 36 languages worldwide, of which he has sold more than 40 million copies. In fact, he is Britain’s biggest selling non-fiction author and would top the overall rankings too, if it wasn’t for a rather successful book series by JK Rowling.

At the peak of his franchise career, Oliver had 42 restaurants in the UK, as well as premises all around world including in Canberra, Sydney, Adelaide, Perth and Brisbane.

He also has a BBQ meat restaurant called Barbecoa and a chain of cooking schools and delis called Recipease which closed at the end of 2015.

Oliver has used his fame to spearhead several campaigns to get the world eating healthier, launching the Jamie's School Dinner campaign and programme which resulted in major overhauls to the way food was served in British schools and championing healthy eating campaigns in Australia and New Zealand.

His #AdEnough campaign pushed for a ban on junk food adverts on TV and online prior to 9pm, along with the removal of advertisements of this kind from public transport.

Two years after Recipease shut in 2015, his traditional British restaurant, Union Jacks, closed its final venue.

In September 2017, Oliver received a devastating phone call while filming an episode of Friday Night Feast with Liv Tyler.

He told the Financial Times about the call, during which he was told his hospitality business, led by Jamie's Italian restaurant chain, was on the verge of collapsing.

The business had "simply run out of cash", he said.

"And we hadn’t expected it. That is just not normal, in any business. You have quarterly meetings. You do board meetings. People supposed to manage that stuff should manage that stuff.

"I had two hours to put money in and save it or the whole thing would go to shit that day or the next day. It was as bad as that and as dramatic as that."

According to The New York Times, Oliver injected £13 million (AUD$24m) of his own personal wealth into the business, but it was still not enough.

In 2018, it was announced the empire lost nearly £20m (AUD$36m) in the previous year.

In May of this year, Oliver announced that his restaurant chain has been put into administration, putting more than 1000 people out of a job.

The company was said to owe creditors nearly £91m (AUD$166m)

"I am deeply saddened by this outcome and would like to thank all of the staff and our suppliers who have put their hearts and souls into this business for over a decade. I appreciate how difficult this is for everyone affected," wrote the celebrity chef in a statement.

All but three of the 25 UK restaurants left in Jamie’s Italian Limited were officially closed and in hands of administrators KPMG.

Reflecting on the failures, Oliver told The Times the past few months have been "the most disappointing of my life".

To The New York Times, he estimated that he mishandled about 40 per cent of his business ventures.

"Probably I was too trusting, which is one of my problems and also one of my benefits,'" he said. "There’s no way to sugarcoat it. I thought I could fix it, but I couldn’t. I can absolutely look at myself in the mirror knowing I tried everything to the last very minute. We ran out of money. It’s as simple as that."

He told The Guardian they planned to turn what's left of his empire in an ethical 'B Corp' that has an equal focus on his passion for issues like animal welfare and childhood obesity, as it does on profit.

Even after such an expensive - and public - failure, Oliver's pockets are still doing just fine.

He has sold 27 million pieces of his Tefal cookware. According to Neilsen Book Research, he sold more than AUD$12m worth of books in 2018 alone. Then there's the TV licencing, and his newest book Veg, released on August 22.

His net worth is estimated at AUD$438m. And he doesn't plan on going anywhere.

"With the restaurants, we had the best of times and the worst of times," he told The Times. "Now I’ve seen a lot, know a lot, smelt a lot, felt a lot. I won’t ever operate in the same way again. But I still think there is a lot more to give. I’m not going to go off into the sunset."