Carefully separate yolks and whites into separate bowls.
Place egg yolks in a large bowl. Add ½ cup (125 mL) sugar. Whisk until pale.
Pour cream and milk into a large saucepan. Set over medium heat until warm and steaming. Slowly whisk about half of cream mixture into egg mixture, then whisk that mixture into cream mixture in saucepan. Set over medium heat.
Cook, stirring frequently, for 1 to 3 minutes until mixture coats back of a spoon or first bubble pops. Strain into a large bowl or container, then cool completely. Slowly whisk in bourbon then Frangelico. Refrigerate for about 1 hour until chilled.
When yolk-bourbon mixture is chilled, beat egg whites with remaining ¼ cup (60 mL) sugar until soft peaks form when beaters are lifted. Whisk egg white mixture into cooled egg yolk and bourbon mixture. Refrigerate until chilled. If making ahead, eggnog will keep well, covered and refrigerated for up to 2 days.
Just before serving, stir eggnog. Sprinkle with freshly grated nutmeg. If you have a kitchen blowtorch, option to use heatproof glasses and brûlée the tops of the nog to add a pleasant meringue scent and pretty colour prior to dusting with nutmeg.
Recipe adapted from: Walsh, Victoria. "Bruléed White Chocolate Eggnog." Food and Drink. Holiday 2014.