"The mouth of the wolf, in the heart of Soho," is how Bocca di Lupo announces itself, and there's a strong whiff of rustic earthiness, of hairy-armpit experimentation about the menu. We all, of course, love the idea of regionalism, its pungent authenticity, its vin-de-pays cred. We've all eaten at obscure trattorias and auberges in Puglia or Normandy and exclaimed, "How wonderful it would be if they cooked this heavenly local dish at the Connaught!" Unfortunately, we've all also eaten in places where a dish of loathsome weirdness (I'm thinking of a lemon-drenched langoustine dusted in cocoa powder, somewhere in Assisi) is served up by an inbred hillbilly whose skills, you fervently hope, never get a London outlet in your lifetime.

Bocca di Lupo is an opportunity to check out some classics (and a few extremes) of Italian regionalism. They've been chosen by Jacob Kennedy, who worked as head chef for Moro for 10 years, was "visiting executive chef" at Boulevard in San Francisco, and opened Konstam in London with Oliver Rowe. His new venture is immediately attractive. Snugly tucked down a dingy Soho side-street, in what used be stripclubland between Rupert and Great Windmill, the restaurant glows with welcome and light.

It's a place of two halves. There's a long bar, of sexy white marble, where 18 diners can sit on leather stools under hot lamps, and watch the chef's theatre before them. The dining-room is dominated by a huge ceiling light in two concentric bands, and is much more homely, with wooden tables and terrazzo flooring. The fine paintings of flowers and food that line the wall are by the LA-born artist Haidee Becker, who turns out to be the chef's mamma.

The menu is like a gazetteer of Italian local cooking: beside each dish, you're told the region it comes from. You learn that the shaved radish, celeriac and pecorino salad is from Umbria, clearly a rather precious region (shaved radish?), while the crescentini with finocchiona, speck and squacquerone cheese, which means fennel-scented pork salami on fried bread with ham and cheese, is a more thick-ear, peasant offering from Bologna.

I tried a small helping (you can order large ones too) of fritto di mare and got a teeny plate of three prawns, five squid roundels and a single soft-shell crab. They'd all been lightly deep-fried and you could eat them whole. The crab tasted of the Venetian Lido that was once its home (or at least home to the recipe), but there was something of the bush-tucker trial about it. I cursed my failure to try the chestnut and porcini soup which a friend had recommended.

My companion went into raptures about her spaghettini with lobster, mussels and ginger (from Sicily), a delicate, angel-hair-pasta dish in which the lobster and ginger, two ingredients seldom hitherto seen together in public, melted into each other's arms at the back of my tongue. It was sublime and you could imagine an Italian aunt knocking it up for lunch in Le Marche.

Main-course scallops from Liguria were magnificently creamy, nicely balanced by their astringent gremolata sauce (lemon, garlic and parsley), but were served on a bed of rocket that seemed a flavour too far. The Tuscan poussin in panzanella was a little eccentric: this panzanella is a melange of toasted bread, pine nuts and raisins, ingredients that crowded round the simply cooked poussin without blending with it. It was an exercise in food-combining rather than flavour-blending. I ordered a side-dish of caponata – a Sicilian classic, combining aubergine, tomato and celery with capers and anchovies, cooked in agrodolce – and was disappointed by the tepid, greasy, overcooked dark strands of strangely sweet aubergine that arrived.

The puddings offered more regional oddness, like cinnamon-and-rice ice-cream from Lazio and nutty ice-cream in a brioche from Naples. Throwing caution to the winds, I ordered the sanguinaccio, because I couldn't quite believe what I was reading: "sweet pâté of pig's blood & chocolate with sourdough bread". It resembled a thick chocolate mousse, surmounted by candied fruit. Spread on a slice of sourdough (such an odd thing to do) and eaten, it seemed merely an intense chocolate pudding, until a whiff of animal fat squeaked at the back of my throat. My companion tried it and gagged. I decided that it went into the category of "interesting, but to be avoided". The good folk of Abruzzo are welcome to it. Regional cuisine can be a wonderful thing, but not when it brings piggy chocolate to the heart of Soho.

There are lots of good things to enjoy in Bocca di Lupo (especially the reasonably priced half-litre carafes of wine), but the menu should be approached with caution – the way you'd approach a group of locals, burning or burying something in the woods outside Palermo...

Bocca di Lupo, 12 Archer Street, London W1. (020-7734 2223)

Food 3 stars
Ambience 4 stars
Service 4 stars

About £90 for two, with wine

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

Side Orders: Forza Italia

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