Wash and drain the cranberries. Discard any that are soft or have broken skins. Let dry on a paper towel. Lightly whip the egg white and add to a large Ziplock bag. Add the cranberries and shake lighly until well coated with the egg white. Add the powered sugar to another Ziplock bag. Add the cranberries and shake to coat. Remove from the bag and store in a tin like candy.
We thought that bluberries, or cherries or grapes, esp. those little champagne grapes would also work well.