In a medium saucepan over medium heat, combine sugar, water, and mint leaves, stirring just until the sugar dissolves; increase heat and bring to a boil. Remove from heat and pour into medium bowl and refrigerate until cold, approximately 2 hours.
Strain mint syrup through sieve set over a bowl, pressing on mint leaves. Discard mint leaves. Mix bourbon, creme de menthe into mint syrup.
Ice Cream Maker - Transfer mixture to ice cream maker, process according to manufacturer's instructions.
Freezer Method - Pour into container, cover, and place mixture in the freezer. When it is semi-solid, mash it up with a fork and refreeze again. When frozen, place in a food processor or blender and process until smooth. Cover and refreeze until serving time.
Serve in parfait glasses that have been placed in the freezer for approximately 1 hour. Garnish with mint sprigs and serve immediately. NOTE: Traditional silver mint julep cups or parfait glasses add a nice accent at serving time.
NOTE: Can be prepared 3 days in advance. Cover and keep frozen.
Makes 4 servings.
Mint Julep Sorbet Recipe: https://whatscookingamerica.net/sorbetmintjulep.htm