I got the idea for this recipe from a comment thread on a news website. It's a fabulous summer refresher--light and tart from the blackberries, rich and sweet from the coconut milk. And the deep purple color is stunning. —ieatthepeach
Combine all ingredients in a blender and puree until smooth. Strain the mixture through a fine mesh strainer, and discard the solids.
Cover the sorbet mixture and chill in the refrigerator for 1-2 hours, or until cold.
Freeze the sorbet mixture in an ice cream machine according to the manufacturer’s directions. Scrape the frozen sorbet into an airtight container and freeze for 1-2 hours, or until it’s firm but scoopable.
The sorbet is best the day it's made, but it will keep in the freezer for about 1 month. If storing the sorbet longer than 24 hours, press a piece of plastic wrap directly onto the surface before covering the container.