Koffmann’s, The Berkeley, Wilton Place, London SW1

Pierre Koffmann, the French master chef, is back – and this time he's bringing his own potato farmer

The smell of fresh paint. The hushed air of expectation. The plethora of staff – suited, booted and keen as mustard. It could only be week one of a major new restaurant opening...

Pierre Koffmann was a three-Michelin-starred master of French cuisine in London for more than 30 years, till he retired from La Tante Claire. Most sixty-somethings would relax into retirement but, last year, Koffmann was lured back behind the stoves for a heralded stint at Selfridges with a pop-up restaurant on the roof.

It must have reawakened his taste (no pun intended) for cooking, as here we are in Koffmann's, his new restaurant in The Berkeley hotel, once the site of Gordon Ramsay's Petrus and Boxwood Café (what a game of musical sauté pans: Koffmann had La Tante Claire in the Berkeley briefly six or so years ago, after selling its original site to Ramsay).

So, to lunch, which is always dicey for a reviewer in the first few days of an opening. The staff are, one assumes, primed for the arrival of either recognisable critics (hello Adrian, Fay, Giles, Jay) or anonymous ones (er, me) who hold on to a menu long enough to make notes.

In charge of the room is Claire, an infectiously enthusiastic woman who turns out to be Pierre's partner. "I don't know what I'm doing here," she confides. "I'm actually a potato farmer." This, as it turns out, is significant.

The sommelier, Mark Botes, is charm itself and despite the demands of my overwhelmingly expense-account fellow diners, is delighted to suggest a couple of wines for my guest, Mr Higgins, who later raves about his Bourgueil "Cuvée Binette", Domaine de la Chevalerie 2007 (£7).

After a quick peruse of the artfully placed books on a mezzanine floor complete with easy chairs, presumably in case any weary diner needs a rest on the way to the loo after a hefty pig's trotter – we settle in at our elegant table and await the gourmand experience. The restaurant's website describes the atmosphere as convivial bonhomie, which is true in a muffled, privileged kind of a way.

Koffmann's food – particularly from the three-course set menu; a steal at £22.50 – doesn't disappoint. My tuna carpaccio with celeriac remoulade is dazzling – translucent discs of very, very fresh fish with deftly judged seasoning and a punchy, creamy spoonful of root vegetable at the centre. I'm in love. Mr Higgins, on loan for the occasion and something of a southern French food specialist (well, he spent a year nesting near Perpignan), gets all misty-eyed over cassolette d'escargots et girolles (£12): a dear little pot filled with bright green, garlicky foam and buttery mash, with a generous helping of snails and mushrooms – interchangeable in shape and size but delivering different taste bombs.

My confit duck is a sticky treat, but on a warm summer's day, perhaps not the best choice; in fact, most of the dishes are the kind of hearty French fare that lends itself best to chilly evenings. Higgins looks askance at his thick tranche of calves' liver Lyonnaise (£22) but, I notice, polishes it all off, declaring it more tender and light than it looks (yeah, but I bet he breakfasted on foie gras in France). He has mash with his liver, I have roast new potatoes with my duck – so far, so standard. But our side dishes include a curl of newspaper (that day's Le Monde, ooh la la!) holding superbly crunchy chips, and lots of them. Chef wants to showcase his partner's produce, it seems, and who am I to complain? I love my carbs.

We make pitiful attempts to stave off furred arteries with melon soup, and a bowl of marinated cherries with fromage frais. The latter might be the poshest Müller Corner I've ever eaten. And the way in which the cherries have been pitted is elegant, can you believe? It's the little details like that, and the stellar quality of the butter, that make this such a class act.

We've failed to have the signature dishes of stuffed pig's trotter or pistachio soufflé (work precludes waiting 20 minutes for the master to assemble this wobbly delight). We've had major food envy over our neighbours' lunch, a whole roast Black-leg chicken (£40) of which they eat just the breast. I want their leftovers to become my doggy bag, but it's not that kind of joint.

Overlook the slightly corporate-luxury vibe that vintage books and mismatched glass lamps can't disguise, and visit Koffmann's before the hordes book it from now till Christmas. Stick to the set menu and good-value carafes of wine and you'd be struggling to find a better deal in Knightbridge, or anywhere else.

8/10

The Berkeley: Book now

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

Koffmann's, The Berkeley, Wilton Place, London SW1, tel: 020 7245 1010. Lunch and dinner, daily. £80 for two with wine (including one set menu)

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Reviews extracted from 'Harden's London and UK Restaurant Guides 2010'. www.hardens.com