Bring all ingredients to a boil in saucepan, reduce heat and simmer, stirring occasionally until the sugar has dissolved.
Remove from heat and let cool 15 minutes.
Place in refrigerator and chill completely.
Strain mixture into a 9-by-9-by-1.5-inch cake pan.
Place in the freezer.
Set a timer for 30 minutes.
With a fork, scrape frozen crystals of granita from the edges of the pan toward the middle.
Repeat every half hour, scraping where needed, until mixture is a frozen, icy fluff, for two to three hours.
This will yield a granita that is puckery-sweet (my taste).
If you want the granita sweeter, you can increase by 1-2 tablespoons sugar.