Coconut-Lime Watermelon Granita

In a small saucepan, bring coconut water and sugar just to boiling; cool.

Remove 1/2 teaspoon zest, and squeeze 2 tablespoons juice from lime. In a blender or food processor combine coconut water mixture and watermelon; cover and blend or process until smooth. Strain into a bowl through a fine-mesh sieve. Stir lime zest and juice into pureed melon. Transfer to a 3-quart rectangular baking dish.

Freeze 2 hours, stirring and scraping frozen mixture from sides of dish every 30 minutes. Cover and freeze, without stirring, 6 hours or until firm. Let stand at room temperature 5 minutes. To serve, scrape across surface with a metal spoon or fork. If desired, top servings with coconut and/or additional lime zest.