In a large bowl, beat together the egg yolks and half a cup of sugar until they turn light in color.
Stir in the milk, heavy cream, bourbon and rum.
In a separate bowl, beat the egg whites with the remaining quarter-cup of sugar until they form soft peaks.
Fold about a third of the egg whites into the yolk mixture.
Serve in punch or tea cups topped with freshly grated nutmeg, folding in more of the egg whites as desired.