Chef Matt Gillan is to leave the Pass restaurant at the South Lodge hotel in Horsham, West Sussex, after a 10-year tenure which saw him retain a Michelin star for five years.
Gillan, who departs the Pass in April, has yet to reveal where he is headed.
Exclusive Hotels and Venues, which owns South Lodge, also declined to reveal who will replace Gillan as head chef.
Gillan joined the restaurant at the five-star country house hotel in 2006 and launched the Pass in 2008. During his time there, the Pass won and retained a Michelin star for five years, along with four AA rosettes.
Last year he appeared in the finals of BBC TV show Great British Menu, receiving straight 10 scores from both the chefs and judges Matthew Fort, Prue Leith, Oliver Peyton and guest judge Felicity Cloake for his main dish Teaching and Preaching.
Gillan said the decision to leave "hadn't been an easy one." He added: "South Lodge and the Exclusive team have given me an incredible platform to showcase my skills and creativity and I feel enormously privileged and proud to have achieved so much throughout my 10 years. I shall be very sad to say goodbye, but the time is now right for me to move on and I am looking forward to my next venture."
Exclusive Hotels and Venues managing director Danny Pecorelli said: "We are really proud of Matt and have enjoyed watching his raw talent and ambition develop over the years into the incredible chef he is today. Matt's experimental originality and playful showmanship has secured the Pass's reputation as a vibrant destination restaurant, so I've no doubt of his future success and wish him all the very best."
Exclusive Hotels and Venues has a track record for attracting award-winning talented chefs, including Matt Worswick at Pennyhill Park, Olly Rouse at Lainston House, Rob Potter at the Manor House and Steven Edwards, former head chef of the Camellia at South Lodge and winner of MasterChef: The Professionals in 2013.
Other hotels in the group include Lainston House near Winchester; the Manor House near Bath, Wiltshire and Pennyhill Park in Bagshot, Surrey.
The group also runs two venues - the Royal Berkshire in Ascot and Fanhams Hall in Ware, Hertfordshire - as well as the Manning Heath and Manor House golf clubs.
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