In typical Ramsay-rant style he told Jay Leno on The Tonight Show, "The food served on behalf of the Queen during a visit to the Queen's London residence was s***, the canapes was shockingly s***. The morsels looked 'prehistoric' and took forever to swallow", he added
"I was trying to get rid of it as I was approaching her because this thing was taking forever to chew. You couldn't spit it out on the carpet for god's sake."
While she was "lovely", he could not say the same for the dishes that were served to her guests.
Ramsay was given an OBE in 2006 for services to the British hospitality industry. The Scot received his gong at Holyroodhouse in Edinburgh, rather than in London.
His comments are unlikely to be welcomed, by chief royal chef Mark Flanagan and his 20-strong kitchen staff who reported also has quite a fiery temperament.
A spokeswoman for Buckingham Palace declined to respond to Ramsay's criticisms.