Bring all but last ingredient to boil in a heavy pot. Reduce the heat to medium low, add the tapioca mixture, and cook 10 more minutes, no more. Remove the cheesecloth.
Cream the soup with an immersion blender, but not completely. Leave about a quarter of it chunky. Adjust the texture and seasonings. Chill completely before serving. Serve as a first course, alone or with a scoop of plain yogurt (dairy free perfect, too), or as a dessert, alone or with a scoop of coconut sorbet. Makes a dozen ample servings.
Variation: Strawberry Rhubarb Soup
Use 10 cups combined strawberries and rhubarb and no other berries. Proceed exactly as above. You might need to add more maple syrup, rhubarb being quite tart.

