Behind my back, Marylebone High Street has been fancying itself as a bit of a foodie enclave. A couple of weeks ago, they had a street party/open day/fête thing — this is what upwardly mobile, commercially aspirational neighbourhoods have instead of community spirit. If you were being forcibly broken in to the international sex trade by a gang of Lascar dwarves on crack in Marylebone, there would be nobody around to call the Sweeney lite community police. But if you want to put up a trestle table and sell fair-trade haddock oil, aromatherapy chillout candles and alluvial Peruvian mud pots, then they’ll be all over you like a big group hug from the Priory old boys’ needle exchange.

So they closed off the street, and there were ethnic and local goods and services, meringue-dancing classes, suck-it-and-see didgeridoo workshops, knit-your-own-bracelet kabbalah starter packs and Portuguese chorizo baps. This is what I love about London. With culture and commerce, it has gently but unequivocally declared unilateral independence from the rest of England. It’s a great example of the truth that politics and politicians don’t lead people — they run after them. Great Britain doesn’t need to devolve from the capital, because the capital has already devolved from Blighty.

I’d gone to Marylebone to see my boy, who’s doing his first bit of work experience. Only it’s not called work experience now, it’s called shadowing, which sounds both euphemistic and sinister; small boys up chimneys were shadowing sweeps. I’d just had a letter from Sarah, a student from Hexham, who madly, deeply wants to shadow me. Darling — you really don’t want to sit in a corner staring at a naked old man, buttocks stuck to an Eames chair, eating pickled herrings with his fingers, trying to download Jethro Tull from iTunes. You could shadow me in Hexham.

Ali, the boy, was helping at Le Pain Quotidien, which I can’t review because it’s franchised by his uncle; other people tell me the bread is the best in London, because it’s made in Belgium. Having beamed with a Micawberish pride at the little breadwinner, I wandered down the road with Christiane Amanpour to La Fromagerie. This is an incredibly impressive shop, a real London treasure. There’s a glass cold room guarded by a morose Frenchman, and inside it’s cool and smelly, like a cross between a catacomb and a discount brothel. We tasted cheese, and I muttered that however much I’m told about the stuff, however hard I concentrate, I never seem to learn anything. “I still know absolutely nothing about cheese,” I said out loud, and behind me a fierce, beady lady in an apron agreed enthusiastically. “You’re right. You know absolutely nothing about cheese. Nothing whatsoever. I wasn’t going to mention it, but I can’t help myself.”

“Do you think she knows who you are?” whispered Christiane.

“You’re not the worst, though. Chefs are the worst. They know nothing about cheese at all.”

“Well,” I said weakly, “cheese trolleys are the biggest loss-makers in a dining room.”

“No, they’re not!” she bellowed, and for an awful moment, I thought she was going to flay me with one of those little Dutch cheese-slicer things. You see, here’s a truth about cheese and the people whose lives revolve around it — they’re all as mad as cheese. People who know everything about cheese know precious little about anything else. Cheese is gastronomy’s trainspotting and stamp-collecting. Cheesists are foodie scientologists. Cheese is weird stuff, its process as close to necromancy as food gets. Its taste and smell repel and attract simultaneously. Its flavours, scents, resonances and fugitive notes are more complex, and range wider, than any other ingredient. Only wine, whisky and tea come close to the oral panorama of cheese. Nations are identified by their cheese: English cheddar, Dutch gouda, Greek feta, German Birkenstock. De Gaulle asked who could unite a country with 265 cheeses, and cheese-eating surrender monkeys was what the Americans called the French — they mistrust French cheese because they can’t import it, for mealy-mouthed, scaredy-cat health reasons. The most depressing, yet telling, question on American menus is: “Swiss or domestic?” Half the world thinks the whole idea of cheese is indescribably filthy, and that we disgusting bovine babysip-curdlers smell of sour vomit. But I’m with Ben Gunn — I know that on the desert island, it would be the memory of the cheese board that would send me tonto. While I was thinking of all of this, I was being given a firm but fair wigging by the cheese-eating evangelist. And I still know nothing.

This week’s restaurant is Arbutus, which sounds like a conflated word for bottom, but is actually a tree from the Mediterranean. The restaurant is on the two-room site that was once Bistro Bruno, Bruno Loubet’s miraculously brilliant restaurant, which, with Alastair Little, made Frith Street a manna nexus. I still miss Loubet’s cooking. Arbutus is a bland, modern room with oblong bits of fussily minimal, textured, backlit chipboard stuck on walls. The one I sat beneath hummed like a lonely toothbrush. It’s full of the sort of Soho people who are responsible for the dystopia of reality television and the despairing, humourless depth of British comic movies. So, if there were any justice, it would be serving botulism. But forget that, because Arbutus has a menu that is an ode to joy.

I started with mackerel and squid hamburger with a BBQ sauce. Sounds tautologous, but it’s a fishcake cooked à la hamburger — oily mackerel, meaty squid, fruity brown sauce. It was pretty damn perfect. Then I couldn’t make up my mind between bouillabaisse and lamb’s tripe parcels filled with pig’s trotters. So I didn’t, and had both. The soup came in two halves — fish and boiled potatoes on a plate, and red-rust broth in a copper pot, with aïoli, rouille and croutons, but no tongue-tying gruyère. Again, impeccable. I’ve never seen lamb’s tripe in a restaurant before, but this is a dish made for critics — sheep’s gut has a strong earth-sign flavour, best described as like morning collie breath. It came with pommes purées and added crispy giblety bit.

After that, the puddings were a bit gay, in the Radio 1 DJ sense, of course. Ile flottante was just too neat and polite, but swam in the best custard I’ve eaten this year, and the cheese was a pair of perfectly presented Frenchish mouldy bits that I’ve naturally forgotten the names of. They came with the ubiquitous huge slab of nutty, fruity loaf. Whoever decided that pauper’s Christmas cake was the only thing to eat with cheese? I noticed on the menu that it came from La Fromagerie. I hope the cheese-eating special-forces woman gets down here and gives them a lecture. There’s a set lunch and pre-theatre menu for £13, and eating off the carte is about half as much again. This is all very accomplished stuff, and it’s just what Frith Street needed.

ARBUTUS

63-64 Frith Street, W1; 020 7734 4545.

Lunch, Mon-Sat, noon-2.30pm; Sun, 12.30pm-3.30pm.
Dinner, Mon-Sat, 5pm-11pm; Sun, 6.30pm-9.30pm

5 stars Cheddar Gorge
4 stars Cracking cheese, Gromit
3 stars Whey to go
2 stars Breaking the mould
1 star Pee-ueh!

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