The Eastside Inn stands on the site formerly occupied by Vic Naylor's, a noisy bar that stuck out, in this foodie district, like a bollard in a herb garden. Next door is Fergus Henderson's legendary St John restaurant. Round the corner is Smiths of Smithfield, in whose "fine dining" sanctum on the top floor I first had the experience of being given a potted biography of the cow whose flesh I was eating. Vic Naylor's, in these rarefied circles, often resembled just a friendly boozer with good snacks. So should a new restaurateur aim to attract the posh diner or the market geezer?

The answer is: both. The Inn's owner is Bjorn van der Horst, an extrovert Dutch-American ("the Bjorn is because my mother was a big Abba fan") who cut his teeth at Greenhouse in Mayfair and was chef-patron of La Noisette, one of the Gordon Ramsay stable. He has designed the Eastside as a restaurant of two classes. Turn right and you're in the "Gastro" section with a hushed, priestly air and a £45-for-three-courses bill; turn left and you're in more down-to-earth territory in the Bistro.

The word comes from the Russian bystro, meaning "quickly," and originally meant a small bar where starving patrons were be-snacked at high speed. And to be honest, the Eastside Bistro doesn't look like a place to linger. The globe lighting is harsh, the banquette seating means you're crammed beside your neighbours, and the long, plain mirror suggests a run-down dance-rehearsal room in provincial France.

The service cheers you up, though. A succession of waiters glided by, bringing wonderfully crusty brown bread, a dish of radishes with butter and flaked salt; volleys of Gallic charm were deployed at my date, Louise. The wine guy made us try his beloved Bergerac, a Dordogne red I never liked until then. It was so jolly, I hoped I'd like the food.

My first reaction to the menu was: stone me, look at the prices. Twelve quid for a salad Niçoise? A tenner for a combination of egg, walnuts and cheese? In a bistro? I soon realised the Eastside wasn't one, despite its stripped-down style. A lot of expertise had gone into making complex things appear plain. Bone marrow and oxtail marmalade was a bold starter which twinned slow-roasted oxtail shards with wobbly oysters of bone-marrow, laid them on toast and gave them a lick of orange zest with horseradish. That was a raft of toast I won't forget in a hurry. The baby squid à la Basquaise were tender as butter and sharpened with smoked paprika, though the accompanying sliced peppers muted the flavours. Not that one wants to pick a fight with a Basque about his regional cooking whims...

The plat du jour was a spectacular plateful of scallops which contradicted the received wisdom that you do as little as possible to the Pectinidae mollusc. These scallops were enormous, perfectly cooked with an entourage of capers and slices of raw fennel with croutons. The combination was magnificent and the buttery juices (with a faint lemony tang) lingered on the tastebuds like a dream.

I expected, from the menu entry "spit-roasted short rib of beef" to be served a thick pink slice of Sunday-roast beef; I continued to expect it even when the waiter explained that it would only be served "medium-rare". What arrived was a blackened tranche of meat that had been braised in juices for hours before being spit-roasted as a coup de grace. I found it overcooked but stifled my complaints as the chef-patron dramatically explained (with the help of his manly frame) how fore-rib and short-rib were different cuts. The baby gem salad with a herb vinaigrette was fine; but disappointment was etched into my brow.

Puddings were OK, if not spectacular. The surface of my crème brûlée wasn't brittle enough and the cream was a touch thick and custardy; my guest's sundae of peanut and chocolate drops in swirly cream was delicious until I discovered there was a rice pudding lurking beneath, and there is simply no negotiating with me about rice pudding. Do not attempt to make me eat one, or I'll cry and make myself sick – a strategy I've employed, when faced with rice pudding, since I was five.

The enterprising Bjorn and his team offer much more careful cooking and inventive flavouring than the word bistro suggests; they also charge a lot more than bistro prices. But if they can sort out this semantic minefield (and persuade enough oligarchs to try their Gastro operation), I suspect they'll be wowing the burghers of Smithfield for a long time to come.

Eastside Inn Bistro, 38-42 St John Street, London EC1 (020-7490 9240)

Food 3 stars
Ambience 2 stars
Service 3 stars

About £100 for two, with wine

Tipping policy: "Service charge is 12.5 per cent optional, of which 100 per cent goes to the staff; all tips go to the staff"

Side Orders: Best bistros

La Buvette

The impeccable retro French staples at this well-priced Richmond retreat include fish soup, confit duck terrine and coq au vin.

6 Church Walk, Richmond, Surrey (020-8940 6264)

Daniel's Bistro

This bistro serves French classics made from local ingredients: don't miss the savoury tarte flambée (£7.85).

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St Petroc's Bistro

The starters at Rick Stein's busy bistro include grilled fillets of red mullet with sauce vierge and toasted fennel seeds (£6.95).

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