British chef, Jamie Oliver admitted he was "very naive" and "hadn't known what he was doing" as he made a tearful trip to his failed Fifteen restaurant for a TV documentary.
The chef, 44, was visiting his pet project where he employed young people from disadvantaged backgrounds for the first time since it closed in May.
In a Channel 4 documentary, Oliver broke down as he surveyed the non-profit London establishment, which shut when his restaurant empire collapsed.
There was rotting food on the kitchen hobs as the sad chef admitted he was "not a businessman" and "very naive". He said: "I was very good at running one restaurant. I opened lots of big restaurants, but people like little restaurants.
"We had these big cathedrals we couldn't fill. The truth is I didn't know what I was doing."
It's 20 years since Jamie Oliver burst on to TV, knocking up a meal for his friends and Jamie Oliver: The Naked Chef Bares All charted his career on Wednesday.
Speaking to presenter Davina McCall, Oliver compared the Fifteen premises in Hoxton to a bombsite as an administrator said they will try to sell its contents, including the tables and chairs.
Oliver said he took the closure of that particular restaurant especially badly.
He spent all his £650 000 (about R12.2-million) earnings from The Naked Chef cookbook on it in 2002.
Oliver, who has children Poppy, 17, Daisy, 16, Petal, 10, Buddy, eight and River, three, with his wife Juliette, said: "It's like a film where a bomb had gone off and everyone's just left."
Struggling to speak, he added: "It's tough. I've been so stressed. It's gone. Over there on the pillar was two plaques from students who died. The staff got paid up until the date and I made sure of it. It is without question the most painful regret to tell staff who you care about and who worked hard for you, that they don't have a job anymore."
Around 1 000 jobs were lost when KPMG administrators closed 22 of Oliver's 25 restaurants in May.
Earlier in the programme Oliver explained to his shocked staff that the business was closing, despite trying to stay afloat by pumping £25 million of his own money in.
Oliver delivered the news in the HQ of his restaurant empire as his business went under.
Standing in front of his staff, the father-of-five said: "Morning guys. It's a really tough one. For many months now I've been walking around and you've said 'hey, Jamie, you all right?' And I've said, 'yeah, I'm all right!' And the truth is no, I'm not f****** all right.
"I'm utterly devastated. Financially, I used everything I could. I used every card, every trick, every contact. We got cocky. We thought everything we did would work. I made massive mistakes and I'll never make them again."
The Jamie Oliver Restaurant Group included 22 Jamie's Italian outlets, plus London restaurants Fifteen and Barbecoa, and Jamie's Diner at Gatwick Airport. Fifteen Cornwall survives.