Step one
Combine the brown sugar, lime juice, fish sauce, water, garlic, and chilies in a small bowl and whisk until the sugar dissolves. Transfer to an airtight container and refrigerate for up to 2 weeks or freeze for up to 2 months. Or freeze in standard ice-cube trays, then transfer the cubes (2 tablespoons each) to plastic freezer bags and freeze for up to 2 months.