3/4 ounce homemade rosemary syrup
5 sprigs of fresh rosemary (for syrup and garnish)
2 ounces Treaty Oak Platinum Rum
1/2 ounce fresh lime juice
1/2 ounce fresh lemon juice
1 egg white

To make rosemary syrup:
Combine one part sugar and one part water in a pot. Bring to a modest boil and add several large sprigs of fresh rosemary. Reduce for 7 minutes; remove from stove and cool. Strain out rosemary and bottle syrup.

Mix all ingredients and shake hard with ice. The cocktail should develop a long-lasting frothy texture. Strain and garnish with rosemary.