Sushinho, 312-314 King's Road, London SW3

Brazilian-Japanese fusion cuisine? No, I've never heard of it either. Pacific Rim cuisine, yes. French-Hawaiian cooking, sure. Anglo-Thai-Vietnamese, OK. But combining the food of Rio and Tokyo on the same menu seems bizarre. Brazil has given the world's restaurants enormous slabs of seared meat, cassava and a bean stew called feijoada in whose black depths disgusting porky intestines can be found lurking. Japan, by contrast, deals in sushi, sashimi, miso, tofu and soy, and emphasises subtlety and visual delicatesse in its toy dishes. The food cultures couldn't be more different. Yoking them together is like persuading Ronaldinho to consort with the comic-strip heroine from an anime film. But I'm told that Sao Paolo houses the largest Japanese population after Japan itself, that it's a century since the first immigrants arrived and that Liberdade (or Japan Town) is crammed with cleverly adapted sushi joints. Some form of mongrel cuisine has clearly become popular in the south American metropolis. What can it be like?

Sushinho, the first such fusion joint in England, looks dark, stark and exclusive from the outside but, once inside, you're enveloped in warmth and welcome. Two amazingly pretty Brazilian girls check your coat and laugh like geishas (what's this called? Charm fusion?). It's tricked out with bamboo struts, drystone walls and a large fern, which give atmosphere to the Formica tables and beige, carpet-weave upholstery. You wouldn't call it Japanese, nor does it awaken memories of crazy nights in Rio.

The cocktail list tries to pull Japanese and Brazilian liquids together, so you're offered a Sakeirinha – like a Caipirinha, Rio's favourite drink, but with sake substituted for cachaca liqueur. My Umeshu Martini delivered a hefty wallop of lychees and Japanese ume plums on top of Hendrick's gin, and was delicious. The food, however, is weirdly hit-and-miss.

The menu is confusing, grouping the starters, soups, salads and tempura in the top left and consigning the sushi and sashimi delicacies to the bottom right. Two sections are confusingly named "sushinho especials" and "sushinho sushi especials" and there's something gratingly precious about the way the side-order vegetables are called "accompanhamentos" – like someone affecting a bogus Mexican accent. The actual specialidad del casa, the titular sushinho, is a small round wheel of sushi with a teeny square of salmon at the centre, surrounded by soft cheese, sushi rice and seaweed, all held in a tempura case. They come in a group of five, and proved very satisfying to a palate bored to death by Yo! Sushi fare. Also welcome were the pimenta prawns, tempura'd in Day-Glo orange with pink sauce, crunchy outside and juicy within; but they were served in such profusion, we could eat only half. "Less," said my date Katrin, "is definitely more here."

I'd been recommended the pumpkin gyoza with truffle, a nicely presented quartet of dumplings, but it proved disappointingly slushy: with pumpkin purée inside and rough pumpkin terrine underneath, there was just too much bloody pumpkin. A side-order of brûléed tuna foie gras brought a rare glimpse of standard-issue sushi, and very delicious it was.

It took an age for the main courses to arrive and, when they did, the restaurant's main shortcoming appeared too. Katrin's pan-fried seabass with sushinho salsa came in five squares on a bed of diced veg, with sweetcorn and tiny cress leaves. The bass squares were crisply cooked, but lacked any presence or flavour, and the salsa bits defied all manipulation by chopstick. We longed for a proper Brazilian sea bass, simply grilled on Ipanema Beach. My crispy pork belly with feijoada bean purée brought half a dozen small cubes of pork, with apple sauce and crackling, on a black-bean tapenade; it resembled a plate of one-bite canapés at a Tunbridge Wells finger buffet. I wished it was a plateful of pork at a Rio market stall, rather than this pointlessly sophisticated bonsai bouche. As if to mock the titchiness of everything, the side-ordered grilled vegetables were like breezeblock slabs of courgettes and red pepper, towering over the miniature main dishes like Stonehenge.

We ended with a "passion brûlée", a last attempt to drag the heterogeneous worlds of kabuki and samba together: passionfruit with soy-sauce toffee, dulce de leche and a white sesame tuile or biscuit. It's just not right, is it? The passionfruit cut nicely through the prevailing sweetness, and the soy and sesame elements kept themselves to themselves (thank God), so it was a qualified success.

Sushinho is a lovely place, and the staff are unfailingly helpful, but the food is neither exquisite enough to suit Japanese palates, nor hearty enough to sate the average gaucho. It's itsy-bitsy, teeny-weeny, fusion-in-between-cuisinie and doesn't really hit either spot.

Sushinho, 312-314 King’s Road, London SW3 (020-7349 7496). About £90 for two, with wine

Food
Ambience
Service

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

Side Orders: Global a go-go

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