A granita is a light, simple, refreshing iced treat that doesn’t require an ice cream maker. Stirring the mixture periodically as it freezes gives the granita its characteristic fluffy, granular texture. Blood oranges are in season right now; they have a wonderful ruby flesh and pleasant sweet-tart juice. You can substitute regular fresh orange juice or tangerine juice. This three-ingredient dessert has an added benefit: One serving provides more than 100 percent of your vitamin C needs for the day.