Combine all of the ingredients in a medium saucepan and bring to a simmer over medium heat. Cook, stirring occasionally, for 5-10 minutes until sugar is dissolved and mixture is thickened.

Add the raspberry mixture to a blender and puree until smooth. Pour the mixture through a fine mesh strainer set over a bowl, pressing down on the sauce until the liquid is extracted. Discard the seeds.

Store in a covered jar in the refrigerator for up to one week.