Whisk the water, sugars, molasses, and spices in a saucepan over medium heat. Simmer for 5-6 minutes, stirring occasionally, until the mixture thickens.
½ cup water, ½ cup light brown sugar, ½ cup granulated sugar, 1 tablespoon molasses, 1 teaspoon ground ginger, ½ teaspoon ground cinnamon, ⅛ teaspoon ground nutmeg