Best Authentic Pisco Sour Recipe

* 2 fl oz (8 parts) Pisco
* 1 fl oz (4 parts) Lime juice
* 3/4 fl oz (3 part) Simple syrup
* 1 Egg white
* 1 dash Bitters
Shake hard or blend with ice and strain into glass. The bitters are an aromatic garnish topping the finished drink, put on top of pisco sour foam. Serve in Chilled tall old fashion glass.