In a large bowl, beat egg yolks until they become lighter in color (can whisk by hand or use a mixer for this). Slowly beat in the sugar, whisking until fluffly.
Combine the milk, cinnamon, and cloves in a thick-bottomed saucepan. Slowly heat mixture on medium heat until it is steaming hot, but not boiling.
Temper the eggs by slowly adding half of the hot milk mixture into the eggs, whisking constantly while you add the hot mixture. Pour the mixture back into the saucepan.
Cool on medium heat, stirring constantly with a wooden spoon, until it begins to thicken slightly, and coats the back of the spoon. It helps to have a condy thermometer, but not necessary; if you have one, cook until the mixture reaches 160 degrees. Do not allow the mixture to boil, or it will curdle. (If the mixture does curdle you may be abot to save it by running it through a blender). Remove from heat and stir in the cream. Strain the mixture through a mesh strainer to remove the cloves. Let cool for one hour.
Mix in vanilla extract, nutmeg and chill.
Optional: Beat egg whites until they reach soft peaks. Add a teaspoon of sugar and continue to beat until they reach stiff peaks. Gently fold into eggnog.