It is noisy theatre; so noisy, you have to turn up your own volume, or be drowned out. You can drink and smoke and generally enjoy yourself. You can even fall out of those notoriously unstable chairs, as I once did, tipping an oyster down my blouse, and simply right yourself and keep on eating.
I wondered if its magic would emerge intact when it reopened week before last after a pounds 300,000 refit. The owners, who don't just own the place, but actually run it, were dashing around the day after Lamont Wednesday with commendable cheer. They had reason: Kensington Place was full.
Many of the confirmed fans filling it up must have been hard pressed to notice the difference. But different it is. The dining room and kitchen are some 20 feet longer. It can feed and seat 40 more people. Recession? What recession?
Yet if Kensington Place wants to fill those 40 new seats day in and out, it is going to have to remember they are there. I sat in one during a second visit, a Saturday lunchtime, and my guest and I quickly realised we were in social Siberia. Blocked by a pillar from the watchful eye of the manager, it got colder and colder as our lunch progressed. Nothing arrived quickly, especially the waiter. Some things, such as mineral water, didn't arrive at all. My companion, excitable when hungry, became mildly frantic, bellowing 'Excuse me]'
Yet to dwell on this one downer after so many ups is to split hairs, like the one my companion found in our olives. The real purpose of my two visits was to write about the food. The chef, 42-year-old Rowley Leigh, has graduated from his tousled Young Turk status of the Eighties. He is now a leading British chef.
His first job was as a short-order cook in Joe Allen's: good training, he says, in which he 'learnt to cook eggs, any style'. He then spent eight years with the Roux empire, moving from Le Poulbot to Le Gavroche to Roux group meat buyer and back to Le Poulbot, where he spent his last three years as head chef. This is the best possible training. Eggs? Easy. Meat: no problem. Puddings: a piece of cake.
When Kensington Place first opened in November 1987, Mr Leigh had inherited a kitchen better suited to a townhouse than a huge bar/restaurant. The dinky workspace, he says, was one reason the food was starter-friendly. With the new extension, he hopes to put more emphasis on main courses and vegetables. Yet even in the earliest days, there was always real finesse to the food.
An omelette, Mr Leigh will say, should be 'smooth as a baby's bottom'. This week mine was exemplary. Flipped constantly in a small pan, it emerged a beautiful little lump, as opposed to long, thin and leathery. It was creamy within, none of its fluffy layers coarsened by over-cooking. The seasoning was no more than fine herbs, all it needed.
There are sure-fire delights that crop up regularly on the menu: grilled baby chicken; beautiful little scallops that have been shown the griddle, served with delicious split pea puree and some zingy mint seasoning; halibut, which can be a tough and difficult fish, but seems to behave at KP. One day I found it tender and simple, topped with earthy, sweated, trompette mushrooms.
Another day halibut was given a treatment I normally associate more with, say, grouse: it was roasted in caul, bedded on bacon and salty cabbage. This was good, but strange. It made fish taste like meat. The steamed version came with snow peas so fresh they could have come straight from the garden. We instantly asked for a second portion.
British cooks seem rarely to partner meat with pasta. Not Mr Leigh. In a particularly simple and robust dish, veal kidneys came in a mustard sauce with nice eggy noodles instead of mash. Some dishes might sound outright weird, such as what looked like 'mackerel tatziki'. It turned out to be tataki, a treatment that involves giving the fish a good pounding.
According to a Japanese friend, the fish is spared violence if it is a bonito, but is seared instead, then marinated in citrus juice, soy, spring onion and vinegar. The mackerel variation is pulverised, then marinated. My fish was garnished with what tasted like toasted, julienned ginger. The upshot was intensely flavoured and so rich it wanted a small lump of rice as a foil.
As another dish, I ordered teal salad. These little wild ducks are meant to be tricky to shoot. They are difficult to cook, and challenging to eat as well. My companion kept insisting I send mine back. She thought it was raw. I kept at it. It was served - quite properly, according to the Larousse Gastronomique - blood rare. But it is strong meat for me, and needed more than a light lacing of plum sauce, and a gutsier plum sauce at that.
As I left, Mr Leigh asked me what I thought of the sauce. If I had had Woody Allen's wits about me, I would have lifted the old gag that it was terrible and there wasn't enough of it.
Puddings are mainly excellent and classic. A grand selection, at pounds 8, could feed four. It includes good, healthy wedges of lemon tart, tart Tatin, chocolate mousse, raspberry ice-cream on a chocolate biscuit and perfect tiramisu. The only clanger to my mouth had a fellow food-writer swooning only days earlier: baked tamarillos.
You might well ask, baked what? Tamarillos: sharp, acidic little fruits, shaped like plum tomatoes, that originated in Peru and are now farmed in New Zealand and America, picked unripe and shipped over. Their sourness might not jar so badly alone, but in the company of classic sweet tarts, moving on to baked tamarillos is rather like going straight from toothpaste to orange juice. On another day, I had two wine-poached pears, cleverly cored but left with their stems, and filled with a spicy cream. Of course, this dish is not new; it is classic for a reason. But the luxury of finding it in a big jazzy bar, where you can spend as little as pounds 15 a head (even a set three-course lunch is only pounds 12.50 on weekdays) or as much as pounds 40 or pounds 50, it feels brand new, even revolutionary.
Kensington Place, 201 Kensington Church Street, London W8 (071-727 3184). Vegetarian meals. Wheelchair access, also wc. Open daily lunch and dinner. Access, Visa, Mastercard, Switch.