Marco Pierre White is acting as a consultant chef for Posthouse, attaching his name to a new-style brasserie to be launched next month.
The Posthouse Hampstead will have the first 100-seat MPW Brasserie, where the average food bill is expected to be £21 per person.
"We are always looking for new ideas and we want to create a neighbourhood restaurant experience," said Martin Kemp, director of conference, restaurants and bars for Posthouse.
The Posthouse Hampstead is undergoing a £1.3m refurbishment of the restaurant, bar, reception and public areas on the ground floor.
A second MPW Brasserie will open early next year as part of the £8m refurbishment under way at the Heathrow Crest.
White is acting as a consultant overseeing menu development, while one of his protégés, Tim Paynes, will liase with White and Posthouse in his role of executive head chef. Paynes has worked with White for more than 13 years.
Posthouse will announce a new head chef in the next week.
White's involvement with Posthouse is an extension of the £2m deal he signed with Granada in 1997. "Both Marco and Granada hope it will lead on to other things," said a spokesman for White.