In 2006 he was a contestant on BBC Two's "Great British Menu", impressing the judges throughout the stages of the competition. Williams interviewed his grandmother about dishes she used to eat as a child before settling on a menu. He beat Angela Hartnett in the regional round, and went on to win the public's vote to cook his fish course of 'Turbot with Oxtail' at Queen Elizabeth's 80th birthday banquet at Mansion House. He retained his crown when he beat Matt Tebbutt in 2007. He has since become a familiar face on Saturday Kitchen, also making appearances on Something for the Weekend and "Market Kitchen".