Kwai Fun Li, 45, of Bishopbriggs, East Dunbartonshire, was initially fined £6000 for hiring the workers between December 2009 and May 2010.
But a court found Li - who employed immigrants at her Kings Lodge Buffet Restaurants in Bishopbriggs and Glasgow - had benefited from her criminal conduct to the tune of more than £1 million.
Under proceeds of crime laws she was hit with a confiscation order for £722,956 at Glasgow Sheriff Court yesterday, following a three-day hearing in July.
The seized money will be ploughed back into community projects.
Li was snared as part of Operation Midstream, which looked at the employment of non-European Economic Area nationals within the UK.
Surveillance was carried out on Li and her business premises over around nine months and searches of the restaurants were carried out.
In June 2011, she pleaded guilty to two breaches of the 1971 Immigration Act and was later fined the four-figure sum.
The Crown Office said confiscation proceedings revealed she had benefited from her general criminal conduct to the sum of £1,064,094.
Assets totalling £722,956 were identified, including over £100,000 in a safety deposit box, and jewellery and watches valued at over £30,000.
Li also held over £300,000 in bank accounts as well as interest in four properties.
Solicitor General Lesley Thomson QC said: "Kwai Fun Li was prosecuted on a summary complaint, pled guilty and fined £6000.
"Little more than 10 years ago, that would have been the end of the matter.
"However, the wide-ranging powers afforded to us by the Proceeds of Crime Act 2002 mean that such cases of 'criminal lifestyle' offending no longer conclude at conviction.
"Those convicted must now account for their unexplained income for a full six years before arrest, and their finances are scrutinised by a team of financial analysts and Crown forensic accountants."
The Serious Organised Crime Agency and the Home Office were also involved in Operation Midstream.
Tony Erne, director of criminal investigations for the Home Office, said: "Not only did Kwai Fun Li knowingly try to flout immigration laws, she also preyed on vulnerable people desperate to remain in the UK illegally and she benefited from her criminal conduct to a significant degree."