Watermelon Syrup

This recipe comes with: Homemade Hawaiian Shaving Ice Cream
Combine all the ingredients in a medium saucepan and bring the mixture to a boil over high heat, stirring constantly to allow the sugar to dissolve. Reduce the heat to medium-low and simmer until the watermelon loses color and the liquid turns a light pink, about 30 minutes. Pour the mixture through a fine mesh sieve and into a bowl. (Do not push hard on solid particles to remove excess liquid.) Avoid dry substances. Pour the syrup (about 4 cups) back into the saucepan and bring to a boil over medium-high heat. Cook until reduced by about half, 10-15 minutes. Remove from heat and allow to cool completely, about 1 hour. Store in an airtight container in the refrigerator for up to 1 week.