Buttered onto toast, added to smoothies, turned into a dip for nachos – but in a cocktail? Most people wouldn’t think of adding avocado to a summer drink. “It works great,” says Dustin Franke, who runs two bars in Berlin and has pioneered what he calls the guacamolita, a quirky variant of the margarita. “The fats and oils of the avocado make it fuller and give it a velvety texture.” Together with fellow barkeeper Luca Simon, he created this avocado cocktail recipe for a refreshing summer drink for the World Avocado Organization (WAO), the association of producers and traders of avocados. “This…