To make the spiced honey syrup. In a medium pot, bring ½ cup water, the honey, rosemary, cinnamon, cardamom, and ginger to a boil over high heat. Boil 2-3 minutes, then remove from the heat. Stir in the orange zest and vanilla. Let cool. This syrup makes enough for about 6 drinks.
In a cocktail shaker, combine 2-3 tablespoons honey syrup, the bourbon, lemon juice, orange juice, and orange bitters. Add ice and shake. Strain into a glass. Garnish with an orange slice and rosemary, if desired.
