Why is cheese essential when the German Chancellor comes for dinner? For millennia, international relations have been massaged by the chefs working inside palaces and state kitchens. The BBC’s Dan Saladino finds out about their unusual vocation and how their food might have influenced some of the biggest decisions in history. He meets Gilles Bragard, the founder of the world’s most exclusive culinary club, Le Club des Chefs Des Chefs, which brings together twenty people who cook for Heads of State. Gilles shares some food secrets, including how the Kremlin's kitchen keeps President Putin’s food safe. We visit the huge kitchens of Hampton Court Palace, where in 16th Century England, wine fountains and extravagant roasted meats were cooked to help Henry VIII impress - and intimidate - foreign dignitaries. We move from there to look at arguably the most powerful cooking place in the modern era - the White House kitchen. Sam Kass, a former chef and close friend to the Obamas, explains how new ideas and even food policies for the future can be cooked up in State kitchens. Plus, we go behind the scenes in the Belgian Embassy in Chile to see diplomacy in action – and talk to professor Stephen Chan of London’s School of Oriental and African Studies about Mugabe’s lavish feasts. We also meet David Geisser, a former Vatican chef and hear insights into the culinary preferences of Pope Francis. We find out if the Vatican leader practises what he preaches about food. Finally, we talk to a journalist in Brussels who has witnessed some recent and dramatic EU meals, including the former British Prime Minister David Cameron’s last supper with European leaders. (Photo: Barack Obama in 2008. Credit: Emmanuel Dunand/AFP/Getty Images)