Ceviche, 17 Frith Street, London W1

Ceviche is quirkily decorated in nostalgic flea-market chic

Peruvian cuisine, it's probably fair to say, is something of an unknown quantity in Britain. In fact, before my visit to Ceviche, a new Peruvian restaurant in Soho, I would have struggled to name a single dish from that country – apart, perhaps, from Lima beans, which don't really count. Here, in the frenzied international zone that is the London dining scene, you'll find Mexican food a go-go, and a growing flirtation with Argentina. But Peru hasn't been invited to the party yet.

First-time restaurateur Martin Morales is determined to change that. A successful entertainment executive, who previously worked for Disney and iTunes, he sold his home to set up a restaurant he hopes will put the food of his country on the map.

Ceviche is (rather unpronounceably) named after the Peruvian national dish of fish, marinated in lime juice, chilli and salt, but there's a lot more to this fun Soho newcomer than raw fish. The menu reflects Peru's diverse culinary heritage, which fuses influences from Spain, Africa and Japan with the plant and cereal-based cooking of the indigenous people. Quinoa is native to Peru – there, that's something else we've all learnt – and that perky little grain pops up here, alongside a host of ingredients so refreshingly unfamiliar, you need a sat-nav to steer your way round the menu.

Our lunchtime visit saw us perching uncomfortably on high stools at the back of a cramped and narrow room, quirkily decorated in nostalgic flea-market chic – vintage album covers, piles of Vargas Llosa paperbacks, framed film memorabilia – all so apparently artless it can only have been the work of an expensive interior designer. Everything on display seems to have been imported from Peru – apart from our lovely waitress, who turned out to be Brazilian.

She encouraged us to kick off with a Pisco sour, Ceviche's signature cocktail, a shortish, frothy blast of deliciousness, somewhere between eggnog and a margarita, that has to be the second most addictive thing ever to come out of Peru.

Then we dived into the ceviches. Now here's the thing about ceviche. It doesn't look great. Not like sashimi, all jewel-bright and delicately fanned out on a beautiful platter. Ceviche, served here in small glass bowls, is basically beige lumps of fish sitting in a puddle of what looks like opaque washing-up water.

But wowser, does it taste good: a punchy, citric explosion of flavour which jump-starts the taste buds and sets the heart racing. We tried two of the eight on offer, one featuring seabass, the other a variety of seafood, and were thrilled by the way in which, once the initial citric blast had receded, subtler flavours emerged, sour, sweet and gently spicy. The super-fresh fish retained all its character and texture, after getting only the briefest exposure to the marinade, known as 'tiger's milk'. Compared to the austere pleasures of sashimi, this is heady stuff.

Also great, from the menu of anticuchos, or grilled skewers, was superbly tender beef heart, which tasted somewhere between steak and liver, and came striped and sizzling from the grill, with a chilli sauce for dipping. "I thought I should let you know," murmured our waitress, "that it is best to eat the heart straight away," a slightly chilling intervention that left us feeling like new recruits to the cast of Twilight.

From the recuerdos, or 'classic favourites', we tried the arroz con mariscos, a paella-like dish of long-grain rice cooked with octopus and squid, distinctively spiced in a way which would no doubt have exiled Peruvians sobbing into their Pisco sours. Also authentic – in that it struck us as a bit weird – was a salad, Causa Santa Rosa, which stacked beetroot and avocado on a cold cake of crushed potato.

The short dessert menu offers a chirimoya mousse (it's a fruit – Google it) which had a touch of the mashed banana about it, and an ice-cream made with another Peruvian fruit, lucuma, which had a lovely burnt-toffee taste. "The only Peruvian products I'm familiar with tend to put you off your food, but that was great," enthused my guest, a semi-retired raver.

Our only complaint – and one that can be levelled at many of the small, informal restaurants that have opened in Soho recently – is that the room is just so uncomfortable, with its cramped tables and spindly bentwood chairs. The menu chummily declares 'esta es tu casa' but if it was mi casa, I'd definitely invest in somewhere comfy to sit. On a busy lunchtime, the din was worthy of downtown Lima. Definitely a place to pop in for a drink and a bite, rather than to spend a long, lingering evening.

The small plates for sharing concept seems to owe more to London fashion than Peruvian tradition. Whether Ceviche authentically reflects the scope of Peruvian cooking, I'm not the person to ask. But with its buzzy atmosphere, reasonable prices and emphasis on big, bold flavours, it's a very welcome introduction.

Ceviche, 17 Frith Street, London W1 (020-7292 2040)

About £25 a head, excluding wine and service

Food ****
Ambience ***
Service ****

Tipping policy: "Service charge is 12.5 per cent discretionary, of which 100 per cent goes to the staff; all tips go to the staff"

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