Grand illusions: St Pancras Grand, St Pancras International, London

This week's venue is more than just a restaurant; potentially it's a national treasure. Thousands of travellers pass through St Pancras every day, entering or leaving Britain on Eurostar. The new St Pancras Grand, with its all-British menu, should be a shop window for our resurgent food culture. If ever a restaurant could be called "destination", this is it.

Searcys, the company behind the station's existing champagne bar, have obviously taken the responsibility seriously; their ambition for the new restaurant is right there in the name, which recalls Grand Central Station as well as the former glories of St Pancras's fabled Midland Grand hotel. The company's CEO has even gone so far as to claim of the restaurant "it will exude the grandeur, mysticism and exoticism of the Orient Express and New York's Grand Central Station". So, no pressure.

They've assembled a ministry of all the talents (including the distinguished chef Richard Corrigan in an advisory role), installed a head chef with a serious pedigree, and spared no expense in fitting out the retro-glamorous dining room. The intention is clearly to create a restaurant that doesn't just cater for travellers, but stands alone as a destination venue.

The station's glorious vaulted spaces were almost completely de-populated when I went for Saturday night dinner at the Grand. With the Eurostar out of service due to fire, the restaurant's clientele was limited to a few solo travellers. Stepping from the upper concourse into the long sweep of the near-empty dining room was a slightly eerie experience, like walking on to an abandoned movie set. Waiting staff heavily outnumbered customers, and any couple planning a Brief Encounter-style tryst would have had to do so under the scrutiny of a brigade of idling extras.

The look of the room is Parisian brasserie by way of New York; monumental orb lights glow from a vaulted ceiling, there are dark leather banquettes and lots of expensively gleaming surfaces, recalling the Conran power-eateries of recent memory. Eurostar trains can be glimpsed through the frontage's plate glass, as though on a flatscreen TV.

The long and flexible menu couldn't be more defiantly British if it painted its face blue and jumped out at you with a stick. The normal brasserie offerings – oysters, shellfish, salads and grills – are joined by a variety of potted seafood and cold meats, including ox tongue and jellied ham with piccalilli. Old cookbooks have been dusted off to find interesting dishes such as braised beef ribs with 17th-century spices and Country Captain, a fruity Anglo-Indian chicken curry, and there are simple gastropub staples, including fish pie, sausage and mash and fish and chips.

There's even a confident nod to retro-camp, in such dishes as the Coronation prawn salad I started with; prawn cocktail given the curry powder and sultanas treatment, and surprisingly successful. Constance Spry, the cook credited with inventing Coronation Chicken, gets a tribute, in the form of a salad named after her. Sadly, it turned out to be just the kind of thing that got British cooking a bad name in the first place; lettuce, tomato and cucumber in salad cream, with radish and some greyish hard-boiled egg. Potted mackerel was served so cold that it resisted the knife.

The mains were respectable rather than knock-out. Smoked Finnan haddock was just the kind of dish to convert a sniffy French visitor to Brit cooking. But a chicken pie from the daily specials was just a casserole under a lid of indifferent pastry. A hotpot that draws on chef Billy Reid's Lancashire roots was properly made with neck of lamb, rather than a leaner cut, but the pickled red cabbage accompaniment was about as appetising as Germolene.

Puddings, all at £6.50, continue in the same adequate but unambitious vein; rice pudding with jam, baked custard tart and an Eton mess to which raspberries had redundantly been added. A bottle of £22 pinot noir from a confusingly arranged all-European list brought our bill to around £40 a head before service. You could spend a lot more – by ordering Sevruga caviar at £75 – or a lot less, by going outside the main meal times, when the menus are crammed with treats, including breakfast-time Manx kippers and for Elevenses, Eccles cake or parkin.

Heartening though it is to see this kind of fare returning to a station restaurant, it's hard to reconcile a place that serves Eccles cake with the "grandeur, mystery and exoticism" that was promised. Certainly we encountered little sign of it, apart from the distant sound of a male voice choir that filled the room at one point. It turned out to be football supporters disembarking from a Manchester train; more Leyton Orient than the Orient Express.

We arrived at StPG hoping for a big night out in the London equivalent of Paris's Le Train Bleu. We left feeling we'd had perfectly decent home cooking. If you were looking to kill time at the station, you'd be glad to find StPG there. But as a destination in itself? London has no shortage of great British restaurants, and while StPG might be Grand, sadly it isn't Great.

St Pancras Grand, St Pancras International, London NW1 (020-7870 9900)

Food
Ambience
Service

Around £40 per head, without service

Tipping policy

"Service charge is 12.5 per cent discretionary, of which 100 per cent goes to the front of house staff. All cash tips go to the waiters"

Side Orders: On the right tracks

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