The Gilbert Scott is located in the travel hub of London's St Pancras. But can it deliver a first-class experience? Lisa Markwell finds out

Anticipation is delicious. But looking forward to an event, a place or a person is such a thrill that it really takes quite a rare treat to live up to it.

The excitement and expectation are such that Marcus Wareing's new venture, The Gilbert Scott, is in danger of being overwhelmed. The marriage of a Michelin-starred chef and a legendary listed building (London's long-unloved St Pancras Hotel, which has been restored to dazzling effect) has had le tout London talking for months, and on opening, the restaurant is booked out almost immediately. In fact, those in the know went to preview dinners and crowed about it on Twitter to alert everyone to their very in-ness (the rest of us take a booking when we can find it).

If The Gilbert Scott has one asset above all others, it is its staff, who are disarmingly helpful, knowledgeable and charming. Marion is our particular guiding light, entertaining and informing us, all with a very light touch.

As this is one of the troika of stellar foodie openings this year (the other two being Heston Blumenthal's Dinner and Jason Atherton's Pollen Street Social), I want to make sure I put The Gilbert Scott through its paces. So it is only Marion who stops me from ordering more than three starters and four side dishes – "You've enough now," she remarks briskly. "Save space for pudding."

Normally I would bristle at such prescriptive service, but her demeanour is so terrific, and her advice so contrary to that one might expect (sell, sell, sell) that we feel safe in her hands.

Backtracking, the menu at The Gordon Scott is another moment of delicious anticipation. It reads like a dream – albeit one of those lengthy ones that seems to go on from lights out till dawn. (There are 13 starters, 14 mains, 15 side dishes and 10 puddings.)

For such an illustrious chef, Wareing gives the credit elsewhere very easily: John Nott's chicken; Queen Anne's artichoke tart and even Lord Mayor's trifle. What has been much reported is that Wareing's idea is to celebrate old English produce and cooking. In a location that once was a major hub for our movements around the country, this makes sense (let's not compare it with Heston's similarly olde English Dinner – they are very different beasts): you have only to walk down one of the long curved corridors and feel the worn tiles underfoot to get a sense of history. (The dining-room itself curves slightly, and has high, high ceilings where the original cornicing can be seen.)

So, anyway, there's a difficulty in choosing starters. We have baked onions (£8) soft and fragrant, with spiced, herby, nutty flavours, and mushrooms on sippets (£8) where slippery nubbins of bone marrow add more density to an already earthy dish. A rich Dorset crab salad has pear and hazelnut shards for contrast and is delicious.

Main courses are where the train runs out of steam (sorry). My soles in coffins is pale in look, texture and flavour. The soft fish on top of soft potato with a soft, vaguely winey sauce is, to use a modern word that I try never to (because it's irritating), "meh". There appears to be a jacket potato skin on top. Hmm.

Mr M has Suffolk stew. It is, for him, just the wrong side of pungent. The anchovy that thickens and enriches the sauce is poorly judged and a bit too fishy. The mutton meatballs themselves are a lovely texture but it never quite comes together. A clod of colcannon would be brilliant to soak up the sauce if only we wanted to, though an oomphy Sicilian red Cerasuolo di Vittoria 2008 chosen for Mr M's mushrooms and mutton by Marion is nigh-on perfect.

Indeed, the ebullient Marion has served us well (in every sense), and we're ready and able to tackle puds. A "jaffa cake" is light sponge with piquant orange and a slick of dark chocolate on the side, while a delicate Earl Grey ice-cream offers the perfect backdrop to the dish.

But top marks go to Mrs Beeton's snow eggs – a confection of poached meringue that looks like a poached egg. "Break" it open and out slips an Everton toffee sauce, muddling with the burnt honey custard. Oh it's scrumptious.

So, when it's good, The Gilbert Scott is v. good. But the arrangement of the tables (too close), the menu (too long) and the judgement of some of the dishes (either too bland or overpowering) do spoil things. If I travelled regularly via the nearby Eurostar I might pop back from time to time (there's a dearth of choices in unlovely King's Cross), but I can't quite love it. And if that fails me the foodie litmus test, so be it. I left feeling just a little bit of anticipointment.


Scores: 1-3 stay home and cook, 4 needs help, 5 does the job, 6 flashes of promise, 7 good, 8 special, can't wait to go back, 9-10 as good as it gets

The Gilbert Scott St Pancras Renaissance Hotel, Euston Road, London NW1, tel: 020 7278 3888 Lunch and dinner daily. £120 for two, with wine