Bourbon Sidecar is a classic cocktail with a twist. It was invented in the 1920s and got its name from an American army captain who drove around in a motorcycle sidecar.
The Sidecar is on the list of International Bartender Association's IBA official cocktails, meaning that there's an "official" definition of the Sidecar. Swap out the brandy for bourbon, and you've got the bourbon version!