1. In a pot off the heat, whisk the egg yolks with half of the sugar (55 g / 1/4 cup) and the cornstarch until smooth. Add half of the milk (500 ml / 2 cups) and the spices. 
2. Bring to a boil while whisking constantly. Remove from the heat and let sit for 5 minutes.
3. Strain the mixture through a sieve into a large bowl. Stir in the remaining milk. Refrigerate for 1 hour or until the mixture has completely chilled.
4. When ready to serve, in another bowl, whisk the egg whites and remaining sugar with an electric mixer until soft peaks form. Stir the meringue and rum into the chilled milk mixture.
5. Serve the eggnog in glasses. Top with the whipped cream. Using a fine grater, freshly grate a sprinkling of the whole nutmeg over the whipped cream. Serve immediately.

Chef’s tip

This is a classic eggnog recipe with a little less alcohol, but you can feel free to add more just before serving! You can also replace the rum with bourbon.