Beat egg white lightly without allowing it to become frothy, and pour into a shallow bowl. Have another bowl ready with superfine sugar. Using tweezers, dip the blossoms first into the egg white and then into the sugar. Use a fine paintbrush to get the sugar into the folds. Shake off any excess sugar, put the blossoms on a wire rack and leave to dry overnight in a warm, dry place. Use to garnish cakes and desserts.