Prepare Your Ingredients: Before you start, make sure you have all your ingredients ready. Squeeze fresh lime juice and prepare the simple syrup in advance. If you're new to making cocktails, remember that fresh ingredients always make a difference!
Combine Ingredients in a Shaker: In a cocktail shaker, combine 2 oz of Pisco, 1 oz of fresh lime juice, 3/4 oz of simple syrup, and the egg white. Don't add the ice just yet!
Dry Shake: Seal the shaker and shake vigorously without ice. This "dry shake" helps to emulsify the egg white, creating that desirable frothy top layer.
Add Ice and Shake Again: Open the shaker, add a handful of ice, and shake again until the outside of the shaker is cold to the touch. This chills the drink and further froths the egg white.
Strain and Serve: Strain the mixture into a chilled coupe or old-fashioned glass. The froth should form a thick layer on top.
Garnish with Bitters: Add 2-3 drops of Angostura bitters on top of the froth. For a decorative touch, use a toothpick to swirl the bitters into a pattern.
Enjoy Immediately: The Pisco Sour is best enjoyed fresh, so serve it right away and savor the blend of flavors.