Eggnog is a chilled custard of egg yolks, sugar, milk and cream, spiked with a decent spirit and dusted with nutmeg. Cognac is the classic choice, though bourbon and dark rum both earn their place. Make it a few days ahead and it only gets better. That is the whole trick, and almost nobody bothers.

Which is a shame, because the stuff in the supermarket carton bears roughly the same relationship to real eggnog that a petrol-station sandwich bears to lunch. Thin, oversweet, vaguely medical. Homemade eggnog is a different animal entirely: silky, gently boozy, perfumed with nutmeg, somewhere between a drink and a pudding you can pour. It takes about fifteen minutes of actual effort, most of which is whisking, and it is one of the few festive rituals that genuinely rewards planning ahead.

A drink older than the word for it

Eggnog did not arrive fully formed. Its ancestor is posset, the warm, spiced milk-and-wine curdle that kept medieval England cosy through long winters, usually fortified with whatever sweet wine the household could afford. When the recipe crossed the Atlantic with British settlers, it met cheaper, more plentiful rum from the Caribbean trade, and later the brandy and whiskey of the colonies. Dairy was abundant in the New World, spirits were cheap, and a cold-weather classic was born. By the time George Washington was entertaining at Mount Vernon, a fearsomely strong eggnog of rye, rum and sherry was reportedly doing the rounds. The man knew how to host.

As for the name, nobody can quite agree. One camp traces "nog" to a strong old Norfolk ale; another to the small wooden "noggin" cup it was served in. Either way, the drink outlived the argument, which is usually the sign of a good one.

The spirit question

Here is where a good eggnog is made or lost. The custard base is rich, sweet and softly spiced, so the spirit needs enough warmth and backbone to be felt through all that cream without bullying it. The traditional answer, and still the best one, is cognac. Its dried-fruit, vanilla and oak character was practically designed to sit in cream, which is why the earliest American recipes leaned on brandy. A straightforward, confident Hennessy VS does the job beautifully, and Rémy Martin VSOP takes it somewhere plusher if you are feeling generous.

If cognac is the tuxedo, bourbon is the good tweed jacket: warmer, sweeter, a little swaggering. A warm, caramel-rich Buffalo Trace makes an eggnog that tastes like Christmas morning in Kentucky. And for the deepest, most molasses-rich version, a measure of Myers's dark rum brings treacle and baking spice that the egg and sugar fall straight into step with. The old colonial move was to split the measure: brandy for elegance, rum for depth. Try one of each and you will see why the habit stuck.

How to make it

For a batch that serves six, separate six eggs. Whisk the six yolks with 150g of caster sugar until pale and thick, the colour of clotted cream. Stir in 500ml of whole milk, 250ml of double cream and a generous grating of fresh nutmeg, then fold in around 200ml of your chosen spirit, a little at a time, tasting as you go. Some people whisk the leftover whites to soft peaks and fold them through at the end for a lighter, foamier nog. It is optional, and a touch more fuss, but it does give the finished drink a lovely cloud-like lift.

That is the entire method. No heat, no custard pan, no danger of scrambling anything, provided your eggs are good and fresh. If raw egg gives you pause, you can gently warm the yolk-and-milk base to 70°C like a thin custard, cool it, then add the spirit; it loses a little of the airy charm but gains peace of mind. Serve it cold in small glasses, with a final dusting of nutmeg and, if the mood takes you, a short stick of cinnamon.

Make it ahead (and why you really should)

This is the part the carton can never give you. A spirited eggnog is not just fine to make in advance, it is markedly better for it. Left to rest in the fridge for a few days, even a couple of weeks, the raw edges soften, the spice and spirit knit into the cream, and the whole thing turns rounder and more harmonious. Food scientists at Rockefeller University once aged a batch for months and found the alcohol quietly saw off any unwelcome bacteria along the way, which is a reassuring footnote rather than a licence to leave it forgotten at the back of the fridge until spring.

The practical takeaway is simple. Make your eggnog this weekend, keep it sealed and cold, and give it a good stir before serving over the days that follow. By the time the guests arrive it will taste like you tried far harder than you did, which is the highest form of hosting there is.

Last pour

Eggnog has an image problem it does not deserve, built entirely on the thin, sugary stuff sold by the litre. Make it yourself, with an egg worth separating and a spirit worth pouring, and it becomes what it always should have been: the most generous drink of the season, somewhere between a nightcap and a dessert. If you are in a cold-weather mood, our notes on how to drink cognac and the best bourbon for when it turns cold will point you at the bottles worth keeping within reach. But pour the first glass of nog with a few days still to go before Christmas, and you will wonder why you ever bought the carton.