The actual birthplace of pisco — a grape brandy created by Spanish settlers during the 16th century — remains a huge point of contention between Peru and Chile, with both laying claim to the invention of the spirit. Nevertheless, one thing remains certain — pisco makes a great cocktail. On my recent trip to Peru, I learned how to make a classic pisco sour from Mariana Gonzalez, owner of Cuesta Serena Boutique Hotel outside of Huaraz. The key to mixing a Peruvian pisco sour is to remember the proportions 3:2:1 — 3 parts pisco, 2 parts lime juice (use key limes, not regular limes, and don’t squeeze too hard as to extract the bitter part of the juice), and 1 part simple syrup. Pour all the ingredients into a blender together with one egg white (two, depending on how many drinks you are making at one time) and a couple handfuls of ice (or however much ice you wish). Blend thoroughly, then pour into traditional pisco sour glasses. Finish the drink off with a few drops of bitters in the center. Enjoy!