In a medium pot, bring 1/2 cup water, honey, rosemary, cinnamon, cardamom and ginger to a boil over high heat.
Boil 2-3 minutes and remove from the heat.
Stir in the orange zest and vanilla.
Let cool to room temperature.
Strain (pressing down on solids to remove as much liquid as possible) into a container and store in the refrigerator. Syrup can be made a week in advance.
In a cocktail shaker, combine bourbon, honey syrup, orange juice, lemon juice and orange bitters. Taste to ensure it has the right sweetness – if not, add an additional tablespoon of syrup.
Add ice and shake. Strain into an old fashioned glass filled with ice.
Garnish with an orange slice and rosemary.
Notes
* I recommend Regans’ Orange Bitters No. 6. * The syrup makes about 3/4 of cup or enough for 6 to 8 drinks (depending on preferred sweetness). * Recipe can easily be doubled or tripled – you may want to use a larger pot.