Courtesy of Smitten Kitchen.
1 large egg, ideally pasteurized [see Note]
1 tablespoon plus 1 teaspoon granulated sugar
6 tablespoons rum, brandy, whiskey, or a combination thereof
1/4 teaspoon vanilla (optional)
1/8 teaspoon ground cinnamon (optional)
4 to 6 tablespoons milk
4 to 6 tablespoons heavy cream
Freshly grated nutmeg
Separate your egg, placing the yolk in one bowl or jar and the white in another.