There is a moment, somewhere between the second sip and the second drink, when the Negroni reveals itself. It is not the first sip. The first sip is the one where you reckon with the bitterness, where the gin and the Campari and the vermouth introduce themselves like strangers at a party you didn't quite mean to throw. It is later than that. It is when the cold has crept into the glass and the orange peel has done its quiet work and the conversation has settled, and the drink, at last, makes sense.

The Negroni is not, strictly, a complicated cocktail. Three ingredients, equal parts, served over ice with a strip of orange. You could teach the recipe to someone in the time it takes the lift to come. And yet, if you've spent any time in the company of people who care about cocktails, you'll know that no other drink generates such reliable, exhausting, occasionally beautiful argument.

This is, in part, the point. A drink as economical as the Negroni leaves nowhere to hide. Get the gin wrong and the whole thing slumps. Get the vermouth wrong and the bitterness feels mean. Get the ratio wrong (and people will tell you to your face that you've got the ratio wrong) and the conversation never quite recovers.

A short history (involving a count, a bar, and possibly a horse)

The legend, and it is largely a legend, goes like this. In 1919, in the Caffè Casoni in Florence, an aristocrat called Count Camillo Negroni asked his bartender, Fosco Scarselli, to fortify his Americano (the lighter Italian aperitivo of Campari, sweet vermouth, and soda) by replacing the soda with gin. The Count had been spending time in London, where the gin was good and the cocktails stronger. Scarselli obliged. He swapped the lemon twist for an orange, to mark the new drink as something else. And the Negroni was, depending on which Florentine you ask, either invented or simply christened.

Like all the best cocktail origin stories, this one cannot quite be proven. There is documentary evidence of the Count, less of the precise moment. But the geography is right and the chronology is right and frankly nobody really minds. The Negroni emerged in Florence in the early twentieth century, which is the historical equivalent of saying the right thing in the right room at the right time.

The recipe, and the war over the recipe

One part gin. One part Campari. One part sweet red vermouth. Stir over ice. Strain into a rocks glass with one large cube. Garnish with an expressed orange peel. That's it. That's the recipe.

Now, the war. There are three things people argue about, and they argue about them with the energy of people who have nothing else to argue about that day. The first is whether equal parts is correct, or whether the gin should be slightly elevated (a 1.25:1:1 split, say) to prevent the Campari from dominating. The second is whether the vermouth should be Carpano Antica (richer, more vanilla-heavy) or a more orthodox Cinzano or Martini Rosso. The third is the gin. Always, always, the gin.

The gin question

Use a London Dry. The juniper-forward backbone of a proper London Dry (Tanqueray, Beefeater, Sipsmith, the kind of gin that tastes confidently of itself) gives the Negroni a spine. A more contemporary, citrus-led gin can work, but tends to disappear into the Campari rather than push back against it. Avoid anything with cucumber, rose petals, or a summer botanical blend. Those gins are made for tonic, not for combat.

A higher-proof gin (Tanqueray No. Ten, Sipsmith VJOP, Plymouth Navy Strength) adds a top note that punches through the Campari's bitterness and gives the drink dimension. If you've never tried a Negroni made with a navy-strength gin, the experience is roughly that of upgrading from prose to poetry.

The vermouth, briefly

Use a sweet red. Not a dry. Not a bianco. The Negroni is built on the interplay between the bitter Campari and the herbaceous, slightly sweet weight of the vermouth. Without it, the drink falls over. Carpano Antica Formula is the indulgent choice; Cocchi Storico Vermouth di Torino is the connoisseur's; Martini Rubino is the entirely respectable pub option. Whichever you use, keep it in the fridge once opened. Vermouth is fortified wine. Leave it on the shelf and it'll oxidise into something flat and sad inside a month.

The variations (handled with restraint)

There is the Negroni Sbagliato (Italian for mistaken Negroni) in which the gin is replaced with prosecco. It is lovely, light, and doesn't, strictly, count as a Negroni at all. There is the Boulevardier, which swaps gin for bourbon and is a different drink entirely, more autumnal, more inward. There is the White Negroni, with Lillet Blanc and Suze in place of vermouth and Campari, popularised by a British bartender at Vinexpo in 2001. It is gentler, more floral, and best ordered after midnight.

All of these are worth knowing about. None of them is the Negroni. The Negroni is the Negroni, and the reason it has lasted a hundred years and counting is precisely that it has refused to become anything else.

Where to drink it

Drink one before dinner. The Italians, who invented the genre, drink Negronis as aperitivi. The Campari is in your bloodstream because it's meant to wake your appetite, not blunt it. A Negroni at the start of the evening primes you for what's coming. A Negroni at the end of the evening is a different beast: more confessional, often unwise.

Drink it sitting down. Drink it slowly. Don't drink it in a flute or a wine glass or whatever the bar has decided is their interpretation. A rocks glass, one large piece of ice, an orange peel rubbed firmly over the rim and dropped in. There is no other correct serve.

Drink it, ideally, somewhere you can see other people. The Negroni is a social drink dressed up as a contemplative one. It is best in a low-lit bar with a marble counter, but it does perfectly well on a sofa with a record on. The cocktail can manage. The cocktail has been managing for a century.

The third drink

Most people stop at one. Two if the conversation is good. Almost nobody, in our experience, makes it sensibly to a third. The Negroni is too high-proof, too uncompromising, too good. Three Negronis is the cocktail equivalent of agreeing to write a novel by Friday. You will mean it, briefly, with all your heart.

But two is, very often, exactly right. Two Negronis, a slow plate of olives, a window onto something interesting, and the evening will rearrange itself in your favour. Three ingredients. Equal parts. A century of small disagreement. The love letter you keep on writing, because nothing else quite says it.