Fancy a Peruvian? The Andean country's cuisine is the ultimate fusion food...

Sorry to land a "next big thing" on your plate, but London, at least, is possibly about to become the latest city – after San Francisco, Miami and Madrid – to be seduced by the cookery of what is known in Paddington Bear books as "darkest Peru", but whose dishes are proving to have the lightest of touches. There are two high-end restaurant openings in the capital early next year, aiming to do for Peruvian cuisine what Thomasina Miers has done for Mexican food with Wahaca. And, as The Wall Street Journal put it last month, noting a Zagat report that there were now four times as many Peruvian eateries across the US as 10 years ago: "Make room Spain and Korea, Peru is having its moment in the gastronomic sun."

In a sense, the cuisine is already with us. "This summer everyone's had a ceviche on their menu, from Angela Hartnett to Yotam Ottolenghi," says Martin Morales, who is naming his new Soho restaurant Ceviche, in honour of the dish. And, of course, there is Nobu, whose founding Japanese chef Nobu Matsuhisa stumbled on his winning formula while running a restaurant in Lima.

Not that Matsuhisa was the first Japanese chef to adapt local Peruvian ingredients, immigrants from the Land of the Rising Sun being just one of several key influences – including Chinese, African, Italian and, of course, Spanish – on the Andean country that was once home to the Incas. "There is a lot of talk about fusion as if it was some kind of novelty," says Gaston Acurio, co-founder of the Astrid & Gaston restaurant in Lima. "But for 500 years, we Peruvians have been creating a fusion cuisine – but slowly and in harmony."

The local ingredients are bountiful, to say the least, with a provenance that stretches right back to the dawn of food history. Potatoes, for example, originated in these parts – and Peruvians not only cook with some 250-300 varieties, they also make tubers the centrepiece of the dish. "There is huge biodiversity," says Virgilio Martinez, chef-patron of Central restaurant in Lima. "We have the Pacific Ocean on the coast, the Andes and we have another world to discover, the Amazon, where as a cook I am still finding new fruits and herbs."

Martinez's as-yet unnamed new London restaurant will open in 2012, probably in Shoreditch, but in the meantime his cooking can be savoured during a Peruvian gourmet food festival being hosted at the London brunch spot, the Cookbook Café. His à la carte evening menu includes a potato tasting dish, papa a la huancaina, as well as such classics as aji de gallina (a chicken and pepper stew with pecans and rice), and, of course, a ceviche. Will there be tastes here that are new to the British palate? "The types of chilli and its different uses are going to be something new," he says. "They aren't hot, but they have a very distinct flavour."

It is the ceviche that is so far taking the firmest grip on British taste buds – and although other South and Central American countries have their ceviches, the dish is thought to have originated in the coastal region of Peru, with limes imported by the Conquistadores. Morales shows me how to prepare it using sea bass and scallops, although other white fish, shellfish or even meats (duck ceviche is popular in northern Peru) can be used. What is vital is that, as with sushi, the seafood should be as fresh as possible.

He begins by making the marinade – the limes squeezed into a bowl, along with a chopped chilli and garlic and coriander leaves. Morales, a half-Peruvian former businessman who helped found iTunes and once managed Joss Stone and Miley Cyrus for Disney, was born in Lima in 1973. "My mother Elsa is from a small mud-hut village in the mountains, some 18 hours by dirt track from the nearest city," he says.

"The area is known for its succulent guinea pig stew, which I was lucky enough to savour every time I visited – my gran bred these unlikely rodents under her kitchen stove and served them at her restaurant. This horrified my father, Roger, who was an accountant from Leicester, who wanted to travel the world so he got a job in Lima working for the mining company. I t was tough times in Peru." His parents divorced when Morales was 11 and when his father was targeted by the Shining Path ("left-wing guerrillas don't like foreigners who work for American mining companies"), father and son moved to England. His maternal homeland has gradually prospered and its well travelled chefs are learning to respect their native cuisine. "In the past 15 or 20 years there have been some great chefs who have said: 'Look, this food is important'," Morales says. "It's really delicious."

One key ingredient – the Peruvian yellow chilli, or aji amarillo – may be hard to source. Morales grows his own. A possible substitute would be to take one medium chilli and blend it with a yellow pepper, so that you had the balance of sweetness and kick that's found in the aji amarillo.

The actual marinating of the fish takes less than a minute – and the result is a beautifully fresh and astringent starter or, served with corn or the ubiquitous potato, a main course. Don't throw away the marinade. Strained, this makes a celebrated Peruvian drink called Tiger's Milk, a supposed aphrodisiac. Add some of the local Peruvian grape brandy, pisco, and you have a Panther's Milk, a veritable mixologist's Viagra by the sound of it.

Pisco is the main ingredient of the Pisco Sour (add lime juice, egg white, sugar and bitters), the national cocktail that Morales hopes will emulate the popularity of the Mojito and the Caipirinha. Those wishing to maintain contact with their senses can imbibe the national soft drink of choice, Inca Kola, made with lemon verbena and the only indigenous beverage in the world that outsells Coca-Cola in its home territory. There's even a popular Peruvian dish called pollo a la Coca-Cola – in which chicken is braised in the Real Thing.

Morales and Martinez want to introduce a different sort of reality to their London restaurants. Apart from ceviche, Morales will be serving anticuchos, marinated barbecued brochettes generally using beef heart. "It's the African influence," he says. "It relates to the time when there was slavery in Peru and the slaves only had offal to work with, so to make it tasty and tender they made this dish, which is served with potatoes and chilli sauce."

Two dishes that are unlikely to be reproduced are the Andean pachamanca, in which meats are placed on heated stones and then buried in earth, and that guinea-pig stew. "They may be a staple in the Andes, but there's no need here," he says.

The Peruvian Gourmet Festival runs at the Cookbook Café at the InterContinental Hotel London Park Lane until 23 October

Martin Morales' sea bass and scallop ceviche

The Spanish conquistadors first brought limes to South America and they soon became a popular means of curing and preserving fish. The important thing here, says Morales, is not to "overcook" the fish by marinating it for too long .

Ingredients:

300g each of freshest possible scallops and sea bass (or other white fish).
6-8 limes
4 tbsp ají amarillo paste
1g fresh ginger, chopped
One clove of garlic
One red onion, sliced
2 fresh red chilli peppers
1 bunch freshly chopped coriander leaves
Salt and pepper

Preparation:

Make the "tiger's milk" dressing with all the ingredients except the fish, red onion, salt and pepper. Set aside (preferably in the fridge).

Chop the cleaned fish and place in a cold serving dish. Sprinkle with salt – to open its pores –and pepper. Meanwhile soak the sliced onion in cold water to reduce its sting and then dry.

Cover the fish in tiger's milk at the last minute and marinate for less than one minute. Drain the juice to drink separately and sprinkle the onion over the fish. Eat immediately.