Rinse a small coffee mug (or white ceramic Tom & Jerry cup) with boiling water to warm it and discard the water.
Add the batter, cognac and rum to the cup and fill with hot milk.
Garnish with a mixture of 2 parts freshly grated nutmeg to 1 part each ground clove and ground allspice.
*Tom & Jerry batter: Separate 12 egg yolks and whites and set aside. In a nonreactive bowl, whip the egg whites with 1 tsp cream of tartar until they form stiff peaks. In a separate bowl, beat the yolks with 2 lb sugar, 2 oz Jamaican dark rum and 1 tsp vanilla extract. When the mixture is completely liquid, fold it into the whites.