Rosemary Simple Syrup is very easy to make and is the perfect addition to a good cocktail. Firstly, add one cup sugar, one cup water and a few rosemary sprigs to a small saucepan over medium heat. Stir together to dissolve the sugar. Then, bring to a simmer. Allow the mixture to simmer for 10 minutes. Remove from heat and let the syrup cool and thicken. Finally, store in an airtight container.