A Pisco Sour is a cocktail containing Pisco (a regional brandy), lemon juice, egg whites, simple syrup, and regional bitters (like Amargo bitters, though Angostura bitters work if regional bitters are unavailable). The national origin of the pisco sour is debated if from Chile or Peru. In Peru, the variety of lemon used has a flavor similar to key lime. Because of this, some recipes call for the use of lime juice rather than lemon juice. In the United States, the drink is usually made with commonly available Lisbon or Eureka lemons.
With the increased availability of Pisco and regional bitters outside South America, the Pisco Sour, like the Mojito and Caipirinha, has increased in popularity in the United States. Peru has a National Pisco Sour Day which is celebrated on the first Saturday of February. Chile's Pisco National Day is celebrated on May 15th.
The roots of Pisco itself reach back to the 1500s and stem from Colonial rule. The Spaniards brought the grape to the region from Europe, but the King of Spain banned wine in the 17th Century, forcing locals to concoct a different kind of alcohol from the grape.
There are at least two common variations concerning the creation of the Pisco Sour drink:
In 1883 Iquique became a Chilean city. The Pisco Sour spread to social clubs and bars throughout the port of Iquique, and from there it spread through the country and beyond. Augusto Pinochet's favorite cocktail was a pisco sour.
Different variations from the original ingredients contained in pisco sour have been produced within Chile. In Santiago can be found iconoclastic pisco sour recipes that include Ají Sour (with a spicy green chilli), Sour de Campo (with ginger and honey), and Sour Haas (with avocados, pineapple, and mint).
The Pisco Sour cocktail is a variation of the Whiskey Sour, invented in the early 1920s by American expatriate Victor V. "Gringo" Morris at The Morris Bar in Lima. The cocktail quickly became a favorite of locals. Soon many of the grand Lima hotels at that time such as The Maury and The Hotel Bolivar began serving pisco sours to their international guests, helping the drink become an international hit.