Ingredients
9 eggs, separated, room temperature
1 1/4 cups sugar
1/2 vanilla bean, halved lengthwise, seeds scraped and reserved
Pinch of salt
4 1/2 cups milk
1/2 cup bourbon
1/4 cup dark rum
1 1/2 cups heavy cream
Freshly grated nutmeg, for serving
Preparation
Put egg yolks, 3/4 cup sugar, vanilla seeds, and salt in a large heatproof bowl. Set bowl over a pan of simmering water, and whisk constantly until mixture is pale and thick, about 5 minutes. Whisk in milk, bourbon, and rum until combined; remove from heat.
Beat egg whites and remaining 1/2 cup sugar in the bowl of an electric mixer until soft peaks form; whisk into milk mixture. In a clean bowl, beat cream until soft peaks form; whisk into milk mixture. Refrigerate eggnog until ready to serve, up to 1 day; whisk before serving. Sprinkle nutmeg over each serving.