The very fashionable Cosmopolitan Cocktail and Sex In The City favourite is the go to party Cocktail and stable of many a bars menu worldwide.The International Bartenders Association recipe is based on vodka citron, lemon-flavoured vodka. The cosmopolitan is a relative of cranberry coolers like the Cape Codder. ... The origin of the Cosmopolitan is disputed. It is widely believed that the drink was created independently by different bartenders since the 1970s.