La Brasserie, South Kensington

As we strolled along Brompton Road on our way to dinner, Anders said, "There's a restaurant down here that's always busy whenever I walk past. We should go there some time." By coincidence - I won't say 'as luck would have it' for reasons which will become apparent - said restaurant in fact turned out to be our destination, La Brasserie, so Anders got his wish rather sooner than expected.

La Brasserie has been in business on the same site in Brompton Cross since 1972 and apart from the addition of a cocktail bar in 2010 - apparently the reason why they have started to invite bloggers and press in to write about the place - it doesn't appear to have changed much in that time. The decor is 'clichéd French brasserie-by-numbers', with red banquettes, checker-board tiles and framed photos of the Eiffel Tower all present and correct. It looks, as Anders observantly put it, like a tourist trap on the Champs Elysées, somewhere designed to reassure unconfident diners that here is somewhere so resolutely and indisputably French that you could not have a Frencher meal anywhere, jamais.

The menu is almost comedically francais too. Ask any mildy xenophobic granddad what he thinks French people eat and he'll rattle off a list including frogs' legs, snails, onion soup, boeuf bourguignon and steak-frites and all of these are indeed available at La Brasserie. In fact apart from the decor and the menu, the only thing that does appear to have changed since the 1970s is the prices, of which some, even in SW3 on what must be an incredibly expensive site, left us rather a bout de souffle.

I started with cuisses de grenouilles persillade, frog's legs cooked in white wine, garlic and parsley, while Anders decided to try the onion soup. Both arrived unnervingly quickly - within just a few minutes of ordering  - and the intense heat radiating from Anders' soup bowl did nothing to dispel the suspicion that it had recently emerged from the microwave. When eventually cool enough to try, it was thin and salty, with no real onion punch and none of the depth and sweetness good onion soup obtains from slow, patient cooking. Anders gave up on it after only a few spoonfuls. The frog's legs smelled and tasted overwhelmingly of garlic; they were nice enough, and tender, but the meat had no discernible flavour of its own.

For our main courses we unthinkingly ordered two variations of essentially much the same dish, in Anders' case the hamburger Holstein -  'chopped steak topped with fried egg, anchovies & capers, frites' - and for me steak tartare, which when done really well (as in proficiently, not 'well', or even 'medium' for that matter, that would be silly) is one of my very favourite dishes.

Alas this was not one of those occasions. What came to the table was so unattractive, so sad and sorry-looking on the plate, that I broke my own rule and took a picture of it, just in case words failed me and I was unable accurately to convey how appalled I was at the green gunge-strewn patty of machine-chopped beef which appeared before me, a black olive plonked on top, two tiny cornichons and two wedges of hard, fridge-cold tomato added as garnish before the whole ugly affair was scattered as an after-thought with parsley.

What even  was that green gloop? The recipe includes gherkins and capers and I gamely - and charitably - trusted that somehow in the food processor these had pureed and coagulated in the mix. I must say it didn't taste anything like as bad as it looked - it was well-seasoned and used good-quality beef - but I still couldn't forgive what had been done to it. Anders' burger - essentially the same thing, cooked - was fine. Not great, but fine. The accompanying frites were bog-standard catering chips, and none the worse for that, but not what you'd expect with dishes costing £17 (the burger) or £20 (the tartare).

In for a centime in for a franc, we gamely pushed through to desserts and oh, how I wish we hadn't. Tarte tatin, a forlorn, dark, compacted looking thing, consisted of sharp, mushy fruit (putatively apple) on a soggy base, served with a scoop of ice-cream - the only properly edible thing on the plate. It was actively unpleasant, also microwaved, and more than two thirds of it was left untouched. Anders' ginger crème brulée was OK, a good creamy filling under a nicely crunchy topping.

No-one noticed or seemed at all concerned that many of our dishes returned to the kitchen less than half-eaten, but then service throughout the evening was - with the exception of the friendly if oddly nervy cocktail barman -  at worst brusque, at best nonchalant, so it came as no surprise that no questions were asked as to our (dis)satisfaction. And for this, a discretionary 13.5% service - yes thirteen-and-a-half percent - is added to your bill.

Whatever I might say about La Brasserie, it will have no effect on its ongoing popularity. A restaurant that has been in business for nigh-on forty years and is, as Anders has witnessed, always busy, does not need good reviews to continue to thrive nor will it suffer from bad ones. It is, effectively, criticism proof. A waitress could slap Fay Maschler with a mouldering ham and there'd still be a 45 minute wait for a table come Friday night while tables stand empty at the superior, and slightly cheaper, Aubaine two doors down.

La Brasserie isn't meant to be a destination for great (or even good) food. It exists for unimaginative wealthy locals and shoppers (and celebrities - Felicity Kendal was there on the night we visited, the most exciting thing about the whole experience) who value familiarity and stability over quality and value for money. "Darling," Anders said consolingly as I wailed uncomprehendingly into the night, "these people are not price-point conscious!"

No, no; I should say they are not.

La Brasserie, 272 Brompton Road, London SW3 2AW Tel: 020 7581 3089 http://www.labrasserielondon.com



I was invited to eat at La Brasserie free of charge by their PR company