Granita is my favorite dessert to make in the summer. It's crazy easy (two ingredients! hands-off cooking!) and crazy adaptable: you can make it with coffee or any kind of fruit juice (citrus is particularly good), or you can add boozy elements. Plus, it's incredibly refreshing. —Sarah Whitman-Salkin
Brew your coffee however you like. Remove the brewed coffee to a saucepan and add the sugar, then cook over low heat until the sugar dissolves.
Pour the coffee-sugar mixture into a 8" square Pyrex baking dish (or whatever shallow baking dish you have). Place in the freezer.
After 40-60 minutes, remove the dish from the freezer and see if any ice crystals have formed around the edges of the dish. If they have, use a fork to gently scrape the icy bits from the edges into the center of the dish, which will still be somewhere on the spectrum from liquid to slushy. Return the dish to the freezer.
Check on the granita every hour for a few hours, repeating the gentle scraping of the ice into the center. After a few hours (depending on how much you're making and how cold your freezer is) you should have a beautiful pile of icy shards.
You can serve the granita immediately, plain or topped with whipped cream. Or you can leave it in the freezer until you need it, using a fork to scrape it up when you're ready to serve.