Separate the egg and reserve the yolk for another use. Place the lemon juice, simple syrup and egg white in a cocktail shaker without ice and shake vigorously for about 15 seconds. Known as "dry shaking," this method of shaking without ice creates a maximum of foam. Chill a glass by filling it to the top with ice cubes (this helps balance the cocktail). Pour the mixture into the bottom of the glass; it should come up about halfway. Pour the cranberry juice slowly over the ice cubes. This keeps the foam on top, the juice in the middle, and the shaken mixture on the bottom, for three lovely layers.
Courtesy Drahos Chytry, Bishop & Baff, Montreal.