Like those world atlas projections based on the cost of air travel, in which America nuzzles up against Ireland but Geneva is shunted to the other side of the world, the moving of the Eurostar terminal from Waterloo to St Pancras has changed the map of the capital for ever, drawing North London to the dead centre of the A-Z and forcing everyone else to regroup around it.

With Paris now only two and a quarter hours from King’s Cross, such places as Westminster, Holland Park, Clerkenwell and even the City of London will have to accept that they are but suburbs of Camden. And South London will, I imagine, simply cease to exist. Since its only function until now has been as a gateway to France.

With millions of Frenchmen now set to emerge, blinking, into the North London sun each year, only nine minutes by bicycle from my home in Kentish Town, I begin to feel a sort of personal responsibility for their eating well on arrival. I sometimes think I should stand outside the station with a sign, pointing them in the right direction – not because I care if the Frenchies enjoy their meal, per se, but because I want them to go home with their tails between their legs, suddenly aware that we eat better these days than they do.

But with the opening of the St Pancras Grand last month, on the Eurostar concourse itself, just opposite the celebrated Champagne Bar, I think I can briefly relax. For I think it is well on the way to becoming as good an example of a modern British restaurant as we have. At least in looks, menu, service and intention, if not always, just at the moment, in the plated article itself. But that’s mere detail; the Froggies will be so bowled over by the time they get their food that they won’t even notice its shortcomings.

The place looks terrific. All the romance and cosmopolitan pizzazz of 21st-century train travel is carried off the rail and in through the doors. The room is vast, the ceiling golden, the hanging ball chandeliers creamy and gigantic – it’s rather Parisian in that way, very fin de siècle bistro (I’m thinking Flo, Bofinger, Julien…). Tables have been laid out to give a maximum of customers that double whammy of corner and banquette that simply screams “great table”, and small islands of seating are divided by cute glass screens that give a bit of privacy without compromising the sprawl of your overall view.

There is really good, dark, unvarnished parquet, dark brown upholstery and crisp white linen. And there are nice, wide aisles for good-looking, well-dressed staff to bustle up and down – bus boys hauling giant trays, Paris-style, for waiters to pull dishes from (consulting little table notes) and place before the right diners without fuss.

The moment you sit, they hit you with a carafe of water and a little steel bucket of mini-baguettes, and then a menu so perfect that it is almost a parody of where restaurants have been going in the past 18 months: a piece of A3 card in eau de nil with 12 headings: oysters; shellfish; smoked and potted seafood; caviar; soups and salads; cold meat counter; fish; meat; vegetarian; side dishes; puddings; cheese.

It’s practically a flag. It could replace the Union Jack on top of Buckingham Palace. You want to take it out in the street and wave it in French faces, crying: “See! See!”

And in among those headings you’ll find dish after dish that you could take outside and beat a Frenchy insensible with: “cold ox tongue with parsley potatoes”; “Constance Spry salad with salad cream”; “smoked Finnan haddock with crushed potatoes, poached egg, grain mustard butter”; “Country Captain chicken curry with poppadums”; “rice pudding with strawberry jam”; “custard tart, butterscotch, Garibaldi biscuits”…

And the wine list is a triumph, too. All this, just like that, from boring old Searcys, the institutional caterers who, apart from the odd blip (one thinks of Tom Ilic’s early days at the Barbican), have never brought us much joy. Perhaps you smell a rat. No, wait, not a rat. You smell a restaurant critic. And your nose does not fail you.

For the St Pancras Grand has been set up in consultation with none other than Fay Maschler, the doyenne of restaurant critics, the mummy of us all, who has now, after quite enough years merely writing reviews (for the Evening Standard), grown tired of screaming into the dark and turned her hand to consulting.

I don’t know much about her new business (we restaurant critics consider it impolite to talk shop), but she is in with another journalist and they are, I gather, offering their two penn’orth to the giants of the hospitality industry in return, one assumes, for quite reasonable oats. And the St Pancras Grand is their first project.

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