Granita is a classic Italian dessert that is very versatile and easy to make. It makes a fantastic cooling fall dessert. Pomegranate season typically runs from October to January. Although a fruit native to the Mediterranean, most pomegranates found in U.S. markets come from California's San Joaquin Valley.
Mix juice, water and agave well with a whisk. Pour mixture into a 9-by-13-inch baking dish. Cover tightly with plastic wrap and freeze approximately 45 minutes, or until icy at the edge of pan. Whisk to distribute frozen portions evenly. Cover and freeze again until icy at edge of pan and overall texture is slushy — about 45 minutes. Stir the granita with a fork and return to the freezer. Stir the granita every 30 to 45 minutes, using a fork, until completely frozen (about 3 hours total).
Using a fork, scrape granita down length of pan, forming icy flakes. When served, the granita should look like a fluffy pile of dry, red crystals. To serve, scoop flaked granita into tall goblets or parfait glasses. Serve immediately with iced teaspoons.