His first job was a pastry chef at Antonio Carluccio's Neal's Yard restaurant, where he first gained experience with preparing Italian cuisine, and developed a relationship with his mentor Gennaro Contaldo.Oliver then moved to The River Café, Fulham, as a sous chef.
It was there that he was noticed by the BBC in 1997 after making an unscripted appearance in a documentary about the restaurant, "Christmas at the River Cafe". That year, his show The Naked Chef debuted and his cookbook became a number one best-seller in theUK.
That same year, Oliver was invited to prepare lunch for the Prime Minister of that time, Tony Blair at No. 10 Downing Street.
In 2000, Oliver became the face of the UK supermarket chain Sainsbury's through an endorsement deal worth $2 million a year.After 11 years the partnership between Oliver & Sainsbury's ended. The final television advertisement was for Christmas 2011.
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In 2003, he was awarded an MBE.
In 2005, he initiated a campaign called "Feed Me Better" in order to move British schoolchildren towards eating healthy foods and cutting out junk food. As a result, the British government also pledged to address the issue. Delving into politics to push for changes in nutrition resulted in people voting him as the "Most Inspiring Political Figure of 2005," according to a Channel 4 News annual viewer poll.
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Oliver's holding company, Sweet As Candy, has made enough profit for Oliver to have been listed on The Sunday Times list of richest Britons under 30.
In June 2008 he launched Jamie's Italian, his very first high-street business venture[clarification needed] in Oxford, England.
It was reported in October 2009 that Oliver is in the process of raising US$22 million to help fund 30 of his Italian restaurants in Asia.
In December 2009, Oliver received the 2010 TED Prize.