In a blender, place the first 3 ingredients and process until smooth and the sugar dissolves.
Add this mixture to a metal pan plus the coconut milk and cream of coconut. Stir with a whisk.
Place in the freezer and after 30 minutes, break up the crystals that have formed. Using the tines of a fork, rake & stir the mixture every 30 minutes, scraping edges and breaking up any chunks as the mixture freezes, until granita is slushy and frozen, about 4 hours.
When is ready to serve, rake a fork through the granita one last time, add your toppings, and enjoy!