The caterer, launched earlier this year with the backing of ex-Compass chairman Sir Francis Mackay, has been charged with developing the venue's corporate event and conferencing business.
Chiddingstone, which is set in 35 acres of grounds encompassing a lake, is undergoing major refurbishment and will be officially relaunched next year. The castle, which dates back to the 1500s, is currently home to the collections of antiquarian Denys Bower.
Restaurant Associates - is expecting income from corporate hospitality to be between £200,000 and £300,000 in the twelve months after the re-launch.
Castle director Alex Lochrane said: "We are very excited about our future here at Chiddingstone Castle. We see Graysons commitment to using high quality ingredients and their attention to detail as very consistent with where we want to be with the castle."
Graysons, which also counts former Compass executives Rowena Edwards and David Cheeseman on its team, picked up its first contract with LGC in Teddington, Middlesex, in March.
By Chris Druce
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