Eggnog is a funny thing. We crave it for one month a year, then never think about it again. When we do crave it, we love to pretend that this sinfully rich drinkable dessert (basically, it's melted ice cream in a glass) is a reasonable and festive pre-dinner aperitif.

Technically, eggnog is cooked custard cream. The French - in a nod to the English passion for it - call it Creme Anglaise. The English themselves call it custard. By any name, it is the base of most ice creams.

In fact, you could just pull a pint of premium vanilla ice cream out of the freezer, let it defrost in the refrigerator, add some booze and nutmeg, and pass it off as custom-made eggnog. Even easier, you can buy eggnog at the supermarket. But the version you make from scratch will be the best you've ever had.

A great eggnog requires few ingredients - milk and/or cream, sugar, vanilla, eggs, nutmeg and (if you like) bourbon, brandy or rum. Many recipes say the eggs should be raw, but I don't recommend it. Not only is it safer to cook the eggs, it also ensures the eggnog develops a thick, rich texture.

You start by beating together the eggs and sugar. Hot milk then is added, but only a bit. This step is called tempering. By mixing a little hot milk into the eggs, you raise their temperature enough to be able to cook them without scrambling them. If you added all of the hot milk at once, you'd end up with unappealing chunks of cooked egg in your nog.

Once everything is combined, concentrate on stirring the custard while it heats until it reaches the proper thickness. There's a chance that the mixture can curdle if you become distracted during this process. Ideally, you're using a wooden spoon. Your goal is to be able to coat the spoon, run your finger through the custard on the spoon's backside and leave a path that doesn't quickly disappear. That's when you'll know it's done. At that point the custard has reached 160 degrees F, the temp at which the eggs are considered safe. As extra insurance against curdling, I have added cornstarch to the custard; this will stabilize the mixture. But if you prefer, you can leave the cornstarch out.

If you do rush and scramble your eggs, throw the custard into a blender. This will help smooth out the texture, though the finished product won't be as smooth as a never-scrambled version. If you want your eggnog to have a lighter texture, whip the heavy cream before it is added. If you're looking to make a seriously extravagant eggnog, add some finely chopped white chocolate to the hot custard. You're welcome to use dark chocolate instead, but the finished drink doesn't look as classically eggnog-y.

BASIC HOLIDAY EGGNOG

Serves 10

4 cups whole milk

1 vanilla bean, split lengthwise

12 large egg yolks

3/4 cup sugar

1 tablespoon cornstarch

2 cups heavy cream

3/4 cup bourbon, brandy or rum

Freshly grated nutmeg, to garnish

In a large saucepan over medium-high heat, combine the milk and vanilla bean. Bring just to a boil, then let stand off the heat for 10 minutes. Scrape the seeds from the vanilla bean into the milk and discard the pod. 

In a large bowl, use an electric mixer to beat the egg yolks, sugar and cornstarch until light and lemon colored, about 2 minutes. With the mixer on, slowly add about half the milk in a stream. Add the egg mixture to the remaining milk in the saucepan. Set the pan over moderately low heat. Stirring constantly with a wooden spoon, heat until the mixture coats a spoon when you run your finger through it and registers 160 degrees F, 15 to 20 minutes. 

Quickly strain the custard through a mesh strainer into a clean bowl. Stir in the cream and bourbon, then cover with plastic wrap and refrigerate until well chilled.

To serve, ladle into cups and top each portion with freshly grated nutmeg.