Whisk together all ingredients in a medium-sized mixing bowl. Spoon into a pint or half liter jar with a tight-fitting lid.
Close and refrigerate for at least 4 hours, but preferably overnight, before eating.
Video
Notes
If you go the frozen route, you will want to back off on the added milk just a touch—by about a tablespoon—since the fruit will release some liquid as it defrosts.