Across Kenya’s ochre fields, farmers are switching coffee and tea for avocados in a bid to profit from increasing European demand for that most instagrammable of dishes. Among them is Simon Kimani, who tends 2ha of avocado trees. "Recently, when the avocado trade started growing up we thought that it is better to plant avocados, that’s how I started," he says, pointing to his first trees, planted less than a decade ago.

Avocado toast is becoming a staple of European menus, says Laura Hannoun, a blogger who has listed the top-10 places to order the simple, hip dish which can set one back €14. "The fair price is between €10 and €11."..