The Nightjar

One night before Christmas, I was lead through an understated wooden door on City Road in Old Street and down a steep staircase into London's best kept secret bar - the Nightjar.

Named after a long-winged nocturnal bird identified by its distinctive warble, whose eyes twinkle like torches at night, the Nightjar is a charming '30s-style speakeasy serving up some of the best-mixed and most beautifully presented rare and revived cocktails in the capital.

Entering the dimly-lit subterranean space, the clock is wound back to an era of gin and jazz. The clandestine drinking den exudes early 20th century glamour, prettified with Art Deco mirrors, a pressed tin ceiling and a glinting copper gin still. Lining the far end are arched booths fashioned from coal cellars, packed with nattily dressed lounge lovers.

Soon after I arrive a hush falls upon the bar, and a man with a mop of mad curls takes a seat at a grand piano and begins tinkering. A whippet-thin lady in a sequined headdress takes to the stage and begins belting out melancholic Berlin jazz. Husky, haunting, hypnotic; she has crowd transfixed. Live music is the Nightjar's lifeblood. The informal salon models itself on an early European cabaret venue, and the live line up on Thursday and Saturday nights ranges from Rhythm and Blues and New Orleans jazz, to boogaloo, ragtime and swing, while vintage vinyl is on rotation late Friday and Saturday nights – the Last Days of Decadence meets the House of Elliot.

Belle Epoque and Prohibition era cocktails using the latest liqueurs, bitters and botanicals abound on the 36-strong menu, displayed in both a gold-bound book and a deck of cards, interspersed with Nightjar heroes: Buster Keaton, Duke Ellington, Josephine Baker and Kiki de Montparnasse. Head mixologist Marian Beke, of The Langham fame, is at the top of his game. Each of the well considered cocktails on the list – including Hemingway's recipe for Islands in the Stream (Santa Teresa Claro rum, lime, green coconut water, angostura bitters and sugar since you ask), are mini masterpieces painstakingly laboured over and exquisitely presented in crystal glassware.

An ideal debauchery den for discerning drinkers, cocktails are taken incredibly seriously at the Nightjar, and thus, take a while to appear at your table. But I assure you they're worth the wait. On my visit I begin with a Ladybird, recommended by Beke. A mix of Santa Terersa Gran Reserva rum, lime, prune, Belgian truffle liqueur, Caribbean spices and orange bitters, the outside of the glass is dotted with chocolate (representing the ladybird's spots), which I dutifully lick off.

Shuffling the deck of cards and pulling one out at random, I move on to a BBC, a dark, decadent and deadly mix of Busnel Calvados VSOP, Becherovka cordial and Absinthe smoke served swimming in a huge ice ball. I've imbibed many a cocktail in my time, and the BBC is utterly unique. Smoky, sexy and seriously hard to drink any more than a sip of at a time, it's like drinking a bonfire sweetened by the blood of nymphs. While I recline languorously in my chair, feeling the effects of the green fairy, my drinking companion enjoys a playfully-titled Wibble, made with Plymouth gin, pink grapefruit, lemon and sugar.

The Nightjar is my secret find of late 2010. The Shoreditch speakeasy oozes laid back charm – its beauty lies in not trying too hard. A word of warning: don't come to the Nightjar if you're hungry. Aside from the customary almonds and olives, the simple bar snack menu includes courgette fritters, saucissons with cornichons, and cow's curd with Sherry vinegar and beetroot relish, but nothing substantial enough to fill up anyone with an appetite bigger than a sparrow.

The Nightjar, 129-131 City Road, London EC1V 1JB, +44 (0)20 7253 4101. Cocktails from £8.50.