We were at a bar in Boston and were brought a cocktail with grapefruit and rosemary simple syrup. We were in love and pledged that we would bring this flavor combination to others. We use a healthy amount of rosemary so that lovely flavor comes through and helps to perfectly complement the grapefruit. To get that ruby color, we also add a dollop of cranberry juice concentrate.

• All-natural, with a 24-month shelf life.