Returning to his column in The Sunday Times Johnson described the company’s downfall as like something from a “nightmare parallel universe”.
In March administrators KPMG said the accounting black hole in the business was £94m, more than double the estimated £40m reported when the potential fraud in its finances came to light in October 2018.
Johnson, who made his fortune expanding restaurant groups including PizzaExpress, insisted he had no knowledge of any accounting irregularities and that he was not the “dominant force” in Patisserie Holdings.
He pointed a finger of blame at auditor Grant Thornton, which oversaw Patisserie Holdings’ accounts, and said it was “astonishing” that “such an eminent firm had the wool pulled very comprehensively over its eyes”.
Writing in the column he said he feared he would become a “pariah” in the business world, and considered leaving the UK after the company fell in to administration in January.
The Patisserie Valerie chain was bought by Irish private equity firm Causeway Capital in February, following the closure of 71 cafes with the loss of over 900 jobs.
But Johnson said he will continue to remain involved in his other business ventures, which include the Gail’s bakery chain.
He wrote: “If I was arrogant at times before, my ego has taken quite a battering since. A very public disaster shatters your self-belief.
“I was far from the only one who had suffered: staff lost their jobs, and suppliers and investors lost money. The whole episode was a business tragedy. A number of us tried to save the company, but in the end the problems were too deep.”
Chris Marsh, the former financial director of Patisserie Holdings, remains under investigation by the Serious Fraud Office.