Loading Chefs have talked of a "macho" working environment where working extremely long hours – much of it unpaid – was the norm. There was "swearing at people all the time" in the kitchen, one former chef said. Another chef said he regularly worked 70 hours a week. He was paid for 38 hours. The underpayment for one chef has been estimated at more than $20,000 a year, or as much as $40,000, according to a recent complaint lodged with the Fair Work Ombudsman.

An ongoing investigation by The Age has uncovered a similar rort at other high-end restaurants fronted by industry heavyweights Neil Perry, Heston Blumenthal and Guillaume Brahimi. The industry award allows management to "buy out" penalties and overtime for a 25 per cent higher hourly rate. However, under the buyout, permanent workers must still be paid more than the award overall. It is a breach of workplace laws for an employer to require excessive unpaid overtime that pushes wages below minimum legal rates. Heston Blumenthal with Neil Perry and Guillaume Brahimi. Credit:Simon Alekna

Mr Ezard, via email, said his restaurants made use of this buyout to compensate award-covered staff for overtime and penalty rates. Loading "If our reconciliations demonstrate that the salary paid insufficiently compensates an employee, the company will pay the difference," he said. Asked how often these reconciliations are performed, Mr Ezard said one is "currently being undertaken and will be on an annual basis". Despite weekly pay for some workers falling below $15 an hour – well below the minimum legal rate – Mr Ezard disputed that they worked unpaid overtime.

"It would be misleading to say that our employees work unpaid overtime given it is an arrangement expressly permitted by the award," he said. Inside upmarket CBD restaurant Ezard Credit:Wayne Taylor The upmarket Ezard restaurant in Melbourne's CBD has been in business since 1999 and has been regularly awarded hats by the Good Food Guide. His other restaurants – Gingerboy, also in Melbourne, and Ezard at Levantine Hill in the Yarra Valley – have also been acclaimed for their food. Mr Ezard, who has appeared on television series MasterChef, stepped down from running his Sydney restaurant Black Bar & Grill in 2017.

United Voice Victorian secretary Jess Walsh said smart businesses knew they could no longer get away with the "salary scam" of unpaid overtime. "For way too long there's been a cone of silence and fear around this salary scam," she said. "But that's lifting now because of a growing chorus of workers ready to speak up and expose all these dodgy practices." Ms Walsh, whose union launched its Hospo Voice offshoot last year, said it was "extraordinary" that the practice continued. Chefs at Gingerboy have been underpaid.

"The smart operators know the ground is shifting and they need to change – and we're already seeing that," she said. The Fair Work Ombudsman said it would conduct enquiries into Ezard and Gingerboy: "We encourage any workers with concerns to contact us directly for assistance.'' The ombudsman also has an ongoing investigation into the Mr Perry-fronted Rockpool Dining Group –Australia's largest high-end restaurant business. Rockpool has already paid back $1.6 million to staff it underpaid for just one year. That is estimated – based on rosters, pay slips and other documents – to be a small fraction of what staff are owed. Rockpool senior executives recently told the Australian Financial Review that the private equity-owned restaurant group could be sold as part of a "strategic review".

Lobby group Restaurant & Catering Australia conceded the industry had a problem that extended beyond isolated cases and was now working with the Fair Work Ombudsman. Celebrity chef George Calombaris has also been forced to repay workers after underpaying them, while Shannon Bennett's Vue de Monde has denied reports it has underpaid its staff. Do you know more? Contact us securely via Journotips