The Christmas spice here comes from falernum, a Barbadian sugar syrup commonly used in tropical drinks. Despite that obvious nod to the summer, tiki recipes and little paper umbrellas, as it also contains ginger, vanilla, cloves and allspice, it hits a lot of the traditional seasonal flavours as well.
This whiskey sour variant is balanced with a dash of cranberry juice to play with the tart lemon (and add a dash of colour), making it perfect for cutting through the rich food of the party season.
Dry shake all ingredients to aerate the egg white. Then shake with cubed ice and strain into a rocks glass. Finish with the bitters.