Theo Randall, chef of the eponymous restaurant at the InterContinental London Park Lane, has taken a minority stake in the Azzurri Group, the owner of the Ask and Zizzi restaurant chains.
Azzurri was created after Ask and Zizzi was acquired from Gondola by private equity company Bridgepoint in December 2014 for around £250m.
The extent of the investment from Randall, who has run the restaurant at the InterContinental since 2006, having previously been head chef at the River Café, is "unspecified", according to The Times.
Randall has already collaborated with Ask for three years on menu development and training and is believed to be looking to develop a second restaurant of his own in Manchester.
Azzurri Group currently operates 112 and 136 Ask restaurants across the UK.
Latest video from The Caterer