Make mint simple syrup. Bring 2 cup water and 2 cups sugar to a boil, and cook until sugar has dissolved. Cool and place in a covered container with 8 mint sprigs. Refrigerate overnight. Fill a silver julep cup with crushed ice. Add 1 tablespoon mint syrup and two ounces bourbon. Stir rapidly to frost outside of the cup. Garnish with a sprig of fresh mint.