Tom Conran is generally held to be a pioneer of the gastropub phenomenon and, on the face of it, he deserves that accolade.

Admittedly, he didn't actually come up with the word 'gastropub' - it was coined by David Eyre and Mike Belben in 1991 to describe The Eagle, their establishment in Clerkenwell - but Conran was quick to embrace the new phenomenon, opening The Cow in Notting Hill Gate in 1995.

Since then, gastropubs have become so ubiquitous that you'd be hard-pressed to find a single watering hole in London serving an old-fashioned ploughman's lunch.

However, the first thing that struck me about The Cow is that it isn't really a gastropub at all, at least not according to the standard definition of the term, which I take to be a pub that serves above-average restaurant food at below-average restaurant prices.

Unlike The Eagle, which does precisely that, The Cow has an entirely separate dining room with its own entrance and reservations line. Not only that, but if you eat at The Cow you can expect to pay well over the odds.

In spite of its spit-and-sawdust appearance - the tablecloths are made of paper and the walls are covered with old Guinness posters - The Cow charges considerably more than most restaurants: in the upstairs restaurant, for instance, a Cornish crab starter will set you back £9 and a main course of côte de boeuf costs a whopping £19.

I avoided the most expensive dishes on the menu, and encouraged my companions to do likewise, but our meal for four still came to £163.40. Admittedly, we did have two bottles of wine, but for a so-called gastropub, that is ludicrously overpriced. And it didn't include service.

To give credit where credit's due, the food wasn't bad. I started with poached ham hock and split pea fritters, which turned out to be the high point of the meal, and followed up with a pot roast of English pheasant, turnip and apple.

All three of my companions elected to begin with the only salad on the menu - a rather hectic combination of poached pear, celeriac, green beans, red onion and walnut - and, of the mains, the tuna got the thumbs up, while the pollock got the thumbs down.

Still, none of us had any complaints about the quantity - our plates were literally overflowing with food. Had I been a homeless person who just happened to have stumbled across a £50 note on Westbourne Park Road, this would have definitely hit the spot.

In a sense, though, this is all irrelevant since the main appeal of The Cow is its bustling, downstairs bar, where a smaller menu is available. It has a slightly down-at-heel, Hibernian quality that has long endeared it to the local trustafarians.

The look and feel is not Irish so much as 'Oirish', that ersatz evocation of the Emerald Isle that is familiar to anyone who has spent any time on New York's Lower East Side, particularly on St Patrick's Day.

Indeed, so accurate is The Cow's simulation of a traditional Irish pub that I suspect many of the regulars would be surprised to learn it was started by a scion of the Conran dynasty 11 years ago. It's no more authentic than Lucky 7, Tom Conran's 'American diner' a few yards down the street.

As if to confirm The Cow's status as the most fashionable pub in Notting Hill, Paul McCartney was spotted there last week, drowning his sorrows in the company of his daughter Stella and her husband Alasdhair Willis.

I was initially told he'd ventured upstairs to dine at the restaurant, but on further investigation this proved to be doubtful. Perhaps he took one look at the prices and ran back downstairs. Given how out of pocket Macca is likely to be after his divorce, that was probably a wise move.