Olivia Rosenman
In 1898, a farmer called Xat de Benaiges, in Valls, Catalonia, dug up his white onions five months after they had been sown and replanted them. His experiment gave birth to the calçot - a vegetable that is registered with the European Union's Protected Geographical Indication scheme and can only be produced in four Catalan counties. It's the champagne of onions.