This is either a mint Gin Sour or a strong gin Mojito depending on how you think of it. If that comparison made no sense and just confused you more, then just know that this drink is amazing. The most popular story is that this drink is named after Chicago, Illinois Southside which was controlled during prohibition by Al Capone and supplied with his “bathtub gin”. Thing is every city has a southside area and the most famous version of this cocktail from Club 21 located in lower/southside Manhattan. Is the Southside cocktail from Manhattan or Chicago? who knows. Any story involving the Al Capone and the Chicago mob scene is fun but the definitive recipe for this drink comes out of New York. Part of the fun may just be the mysterious nature of this drinks origin, but regardless this prohibition era drink is amazing.