In the bowl of a stand mixer, beat the egg yolks until they lighten in colour. Gradually add the 1/3 cup sugar and continue to beat until it is completely dissolved. Add the milk, cream, bourbon and nutmeg and stir to combine.

Place the egg whites in the bowl of a stand mixer and beat to soft peaks. With the mixer still running gradually add the 1 tablespoon of sugar and beat until stiff peaks form.
Whisk the egg whites into the mixture. Chill and serve.