Aubaine, 37-45 Kensington High Street, London W8

Though it seems like a clever portmanteau word, yoking together "auberge" and "urbane", Aubaine is French for a godsend, a fortunate windfall or a stroke of luck. The owners have struck it lucky in London three times already, opening branches of their chain and flourishing in Brompton Road, Regent Street and the Shoe Galleries at Selfridges, despite online reports about the Parisian rudeness of the staff.

Aubaine's owners started out as patissiers, after recoiling from the horror of English pain blanc typique, and an impressive display of seedy and raisiny breads is the first thing you notice at their new Kensington address. The second thing you notice is that the restaurant is pitched some inches below street level – as if the floor sank after a small earthquake, but the lunchers were too British to complain. The third thing you notice is that it's crammed with Kensington Ladies.

Every table, it seemed, was awash with London W8 dames in their forties and fifties, their well-bred thighs tucked into jeans, their lovely throats warmed with lambswool scarves, Brora polos, shawl-necked cardigans, their hair carefully unruly, their conversation full of pointing fingers and effortful laughter. Six early-thirtysomethings occupied a table by the entrance, resembling an early episode of Sex and the City. An oversized Miranda Hart clone was lunching her snow-haired mama. What strikes you about the clientele isn't just the prevailing X-chromosome; it's the sense of entitlement they bear, as if they've been lunching here for years, though it's only been open a few days.

The décor is faux-rustic, possibly ordered from the Baileys mail-order catalogue. The floor is wooden, ditto the painted chairs, the tables (some zinc-topped) and the cupboards that house wine bottles behind wire-mesh doors. Wood-framed mirrors line the walls. Plastic olive trees in the windows obscure the view of the London buses grinding past outside and might convince a very impressionable person that they were in Provence.

The menu is unadventurous French cuisine, and the dishes come in twos, as if seeking entrance to Noah's Ark: two goat's cheese starters, two carpaccios, two tendril-waving seafoods, two mildly exciting vegetarian dishes (artichoke with mozzarella and tomatoes, winter vegetables with duck egg and truffle potato). Among the mains were harmless fish dishes (lobster, cod, seabass, sole) for the laydeez, some butch steaks, "aged" for 35 days, and corn-fed chicken, but nothing suggestive of a signature dish, or of anything that would test the skills of a first-rounder on Masterchef: The Professionals.

The French waiter wasn't much help with the choice. When I asked what exactly was going on, apart from chicken, in the chicken pot-au-feu, he looked at me as if tired of such fatuous enquiries. "Ees 'ome-made," he finally ventured.

What made my jaw drop was the prices. When my guest Madeleine had the roast scallops with Jerusalem artichokes and cep confit, I expected more, for 16 quid, than the four anaemic lumps of shellfish on their beige purée. It was, however, delicious ("Very sweet and tender scallops," she said. "Comforting but not heavy on the carbs"), as was my octopus carpaccio. Pinkish slivers of cephalopod, accessorised by salad leaves across which a single chilli lay like a long green threat, it was perfectly dressed.

The main courses arrived with dizzying speed. Madeleine, having scarcely drawn breath after the artichoke mash, regarded her roast cod and red-wine-braised squid with a weary eye. But soon she was enthusing about its pan-fried, lightly seared, charcoaled fishiness, how well it balanced the fennel, all of it soothed by a green pea sauce. My free-range pork chop was delicious, bonding with the soft chunks of lightly-cooked apple like Julie Andrews encountering the junior von Trapps.

In spite of my earlier sneers about the décor and clientele, Aubaine was working out well. But the pudding course cancelled out some of the goodwill. While we could in theory have chosen ice-cream (yawn), sorbet (nod off), fresh fruit (zzz), or the cheese platter (snore), they urge you to try the lovely cakes displayed on a plate. You can choose an éclair, a raspberry tart, chocolate mousse, orange macaroon or millefeuille. We felt the selection suited late teatime, and when we discovered the pear and almond clafoutis was slabby and boring, we asked whether cakes are really the perfect pudding for W8 ladies. The food is fine at Aubaine, but you have to conquer the feeling that you're being put through a process, rather than being treated to an experience.

When we were leaving, I asked the waiter to let me have a copy of the menu. I always take one home, to check the dishes when I'm writing the review. The waiter returned and said, "I asked the boss about the menu. 'E say 'Nao'." Well, thanks a lot. Was it a sign that they were worried about the dullness of the list? Or just of their being bloody-mindedly French?

Aubaine, 37-45 Kensington High Street, London W8 (020-7368 0950)

Food
Ambience
Service

About £120 for two, with wine

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: Vive la France

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