St John Hotel, 1 Leicester Street, London WC2

The new St John Hotel has been a long time coming. The original autumn opening date passed, seasons changed, bookings were accepted for March and then cancelled, and still the builders laboured on. All we needed was for Kevin McCloud to pop up murmuring "if only Fergus and Trevor had employed an architect..." and it would have made a perfect episode of Grand Designs.

St John does have an architect, of course, in the form of Fergus Henderson, architect-turned-chef, turned patron saint of Modern British cooking. And now he and his gutsy, nose-to-tail style of cooking are finally back in Soho. It was not far from here, in the rackety French House Dining Room, that Henderson embarked on his earliest culinary adventures, before his long working partnership with Trevor Gulliver took him east, to Clerkenwell and St John.

This new hotel – really a restaurant with rooms – is a bold venture from a team who could be excused for putting their trotters up and quietly enjoying their success. It is – how to say this politely – in a truly nasty part of town, where the human traffic jam of Leicester Square spills over into Chinatown. This corner might have been given a lift by the arrival of the glam new W Hotel, but it's still hell on wheels, rammed with drunks, confused tourists, and the unsavoury types who prey on them.

An oasis of pure-white calm in this tawdry human jungle, the St John Hotel occupies the grand old building which housed the Italian-run fish restaurant Manzis, one of the last survivors of pre-war Soho. The evocative signage on the façade has been retained, but otherwise there's nothing recognisable about the place.

There are bedrooms, as there apparently were at Manzis, for full overnight stays or post-lunch trysting. There's a student union-ish bar on the first floor, up a twisty staircase that already looks a bit scuffed. And there's a canteen-like dining room which clearly shares DNA with the original St John. White walls, white-clothed tables, schoolroom chairs, and at one end, an open kitchen staffed by a bunch of cerebral chefs who look as though they could field a useful University Challenge team.

Dining on opening night (more by accident than design), we were seated next to a large, naked window, leaving us showcased like a hard-to-shift window display in Amsterdam's red light district. With shoals of young women in tiny skirts tottering past outside, and an actual red light visible across the road, it brought a new meaning to nose-to-tail eating.

With its close-packed tables and harsh acoustics, it's an unforgiving space; all the comfort is to be found on the plate and in the glass. Head chef Tom Harris has come from St John, and his daily-changing menus here are a chip off the old block, not that you'd find anything as banal as chips on them.

As fans of the house style know, behind St John's unpromisingly terse menu descriptions are dishes that not only taste good, but are also in perfect good taste. A starter of sliced veal tongue and waxy new potatoes was lifted by a perfectly pitched mustard-sharp dressing. Crumbed skate cheeks, crisp, scampi-like nuggets, came with tartare sauce for dipping. A side salad of punchily-dressed watercress was so iodine-rich it practically leapt off the plate.

In a departure from St John tradition, at dinner there are several main courses to share between two – on the night we visited, they included suckling pig ("It's the face," I heard a waiter explaining to a neighbouring table).

We shared a dish of bacon and beans, largely out of curiosity as to how they could charge £28 for what was really posh baked beans. Essentially cassoulet without any of the funky stuff, it was an enjoyable, if samey dish.

Puddings have always been a highlight at St John; here an apple shortcake tart, somewhere between a crumble and tarte tatin, served with bay leaf ice-cream, and a rhubarb sundae, were both good. But after paying a bill that nudged £35 a head for food alone, we didn't leave feeling we wanted to make a regular date with St John Hotel.

The pricing might seem a bit steep in places (the all-French wine list doesn't offer much choice below £30 a bottle) but this is a prime slab of real estate. And neither location or pricing seemed to deter the Modern British crowd who were still pouring in at 11pm.

London is becoming more like New York, where people will crawl through a warzone to get into a happening restaurant, and the fact that the hotel serves dinner until 2am, and breakfasts from 7am, will be a draw. But Soho now offers many more exciting places to eat well than it did when the SJH was being planned, most of them cheaper and more salubriously positioned. So I can't quite call it. Instead I'll leave you with a Kevin McCloud-like final thought. So much passion has gone into this project. Fergus and Trevor have built the place they want to live in, without compromising their vision. And in the end, that's all that matters.

St John Hotel, 1 Leicester Street, London WC2 (020-7251 0848)

Food
Ambience
Service

Around £65 a head including wine and 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"

Side Orders: Room service

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