In your cocktail shaker with ice, combine all ingredients.
Shake vigorously for about 15 seconds.
Fine strain from one tin to the other, removing the ice and setting aside.
Shake again in a "dry shake" without ice for another 10-15 seconds to build up a frothy texture.
Double strain into a chilled Martini glass or coupe glass.
Garnish with ground nutmeg and/or a bit of cinnamon-- or even a pinch of ground pumpkin spice if you need a little more flavor. (We used cinnamon.)