Hawksmoor, the premium steakhouse, is close to selling a minority stake to the private-equity firm behind London's Groucho club.
Investors in Hawksmoor, which has four restaurants in London, are in exclusive talks with Graphite Capital, the former owner of the Wagamama noodle chain.
The food entrepreneurs Will Beckett and Huw Gott opened the first restaurant in 2010 and it has quickly attracted an army of steak fans.
Underdog Restaurants, which operates Hawksmoor, nearly tripled pre-tax profits to £1.2m over the year to December 2011, according to its latest accounts. The restaurant's turnover rocketed from £3.7m to £10.6m over the period.
It is unclear how much Graphite is looking to pay for a minority shareholding in Hawksmoor but it will be a multi-million pound sum.
Graphite acquired the Groucho Club, the private members' club that the artist Damien Hirst and actress Sienna Miller have frequented - in 2006.
Last year, Graphite invested £21m in Rex Restaurant Associates, the parent company of London's upmarket Wolseley restaurant.
Graphite and Hawksmoor did not return calls today.