Combine all ingredients in a blender and blend for one minute or until quite smooth.
Transfer the liquid to a wide baking dish, then put in the freezer.
That cool mint and that hot serrano play well together when they’re all frozen! Granita needs a little eye on the clock while its freezing, but it’s pretty darn forgiving, especially when honey is the sweetener as it helps the liquid not freeze too hard. It’s also a superb way to use up that extra mint that starts taking over the garden this time of the year!