For the sour mix: Add the lemon juice, lime juice, sugar and water to a pitcher and stir. Let cool before using.
For the blackberry puree: Puree the blackberries and sugar with 1 cup water in a blender until smooth.
For the cocktail: Put the bourbon in a cocktail shaker with ice, add 2 ounces of the sour mix and 1 ounce of the blackberry puree and shake vigorously. Strain into a rocks glass with ice.
This recipe was provided by a chef, restaurant or culinary professional. It has not been tested for home use.
Recipe courtesy of Luke Hampton, Dram Whiskey Bar, Mountain Brook, AL