The Skeleton Key is a refreshing cocktail made with Bourbon Whiskey, Elderflower Liqueur, Fresh Lemon Juice, Ginger Beer and Angostura Bitters. The drink has a balance of sweet and sour flavors, with a hint of spice from the ginger beer. The bourbon whiskey gives it a smooth and slightly smoky flavor, while the elderflower liqueur adds a floral sweetness. The fresh lemon juice brightens up the drink and gives it a tartness that helps cut through the sweetness. The exact origin of the Skeleton Key are unknown, but it is thought to have originated in the United States sometime in the early 1900s. The first known recipe for the cocktail was published in William Boothby's ""The World's Drinks and How to Mix Them"" in 1908. The Skeleton Key became popular during the Prohibition era, when many people were looking for ways to make their own alcoholic beverages at home. Today, the Skeleton Key is still a popular cocktail, and is often served at parties and events. If you're looking for a delicious and easy-to-make cocktail, the Skeleton Key is a great choice.