Free-range eggs from Prince Charles's farms and British favorite Bakewell Tart were among dishes to be served up by celebrity chef Jamie Oliver to world leaders attending the G20 summit in London today.

Oliver, nicknamed “The Naked Chef” after his first TV series, was to cook the three-course meal last night at 10, Downing Street, the prime minister's official London residence. He will be helped in the kitchen by disadvantaged youngsters from his “Fifteen” charity restaurant.

A champion of fresh seasonal produce, Oliver was to use ingredients from all corners of Britain to feed the leaders of developed and emerging nations.

On the menu was organic farmed salmon from Shetland, Scotland, with samphire and sea kale. The main course was shoulder of lamb from north Wales with foraged wild St George mushrooms and mint sauce.

Dessert was hot Bakewell Tart with custard made with free-range eggs from Prince Charles's Duchy of Cornwall farms.

"I'm very, very proud of my country and its food traditions, and I know that the guests at Downing Street will be in for a real treat," the chef said in a statement.

Oliver has used his celebrity status to establish a series of charity restaurants called Fifteen. Young people who may have been homeless, unemployed, or overcoming drug or alcohol problems, are trained to become chefs.

Graduates of Fifteen and one current apprentice were among the eight chefs helping Oliver in the Downing Street kitchens.

Oliver has cooked at Number 10 Downing Street twice before - when former Prime Minister Tony Blair entertained his Italian counterpart Massimo D'Alema and his Irish counterpart Bertie Ahern.

Using well-known chefs for such occasions is traditional.

When former US president Bill Clinton and his wife Hillary came to London, Blair took them to Terence Conran's restaurant Le Pont de la Tour at Tower Bridge near the Thames river.

Questions:

1. Where were the free-range eggs from that were used in the Bakewell Tarts?

2. What is the name of chef Jamie Oliver’s series of charity restaurants?

3. Name the two visiting world leaders that Oliver has cooked for before at Number 10 Downing Street?

Answers:

1. Prince Charles's Duchy of Cornwall farms.

2. Fifteen.

3. Massimo D'Alema and Bertie Ahern.