This was a recipe that was born out of me not wanting to be wasteful. Whilst making some watermelon juice, I didn't want to just throw out the pulp so I left it a little juicy, added some simple syrup, and then popped it in the freezer. It's now one of my favorite summertime treats.
If you are making the granita ahead of time, it will firm up quite a bit in the freezer. I recommend "defrosting" it
By the way, this is also a great base for making watermelon margaritas. Splash in a little tequila and serve in a salt-rimmed glass! —Rach Kim