Combine the water and sugar in a small nonreactive saucepan. Bring to a boil, stirring occasionally to dissolve the sugar. Cool the syrup. Rinse the berries. Wrap and refrigerate a few attractive ones to garnish the granita. Hull and puree the remaining strawberries in a blender. Measure 2½ cups strawberry puree and add to the cooled syrup. Stir well to combine.
Pour the mixture