Place basil leaves and Basil Simple Syrup in a julep cup or an 8- to 10-oz. glass. Gently press leaves against sides of cup with back of a spoon to release flavor. Pack cup tightly with crushed ice; pour bourbon over ice. Insert straw, and place basil sprig directly next to straw. Sprinkle with powdered sugar, if desired.
Note: For testing purposes only, we used Woodford Reserve Distiller's Select Bourbon.
Fresh Mint Julep: Prepare recipe as directed, substituting mint leaves for basil leaves, Mint Simple Syrup for Basil Simple Syrup, and 1 small fresh mint sprig for basil sprig.