The Roof Garden is a pale, Nordic-style restaurant at the top of the glorious Pantechnicon in Belgravia — formerly a bazaar — opposite a Waitrose I didn’t know existed. (Waitrose seems too human for Belgravia. Food seems too human for Belgravia.) This thrilling building, which should be a library — it has Doric columns — is instead a collection of restaurants, shops and what I think are called ‘outlets’ (a Japanese café; something called, gnomically, ‘Kiosk’), all celebrating the ‘playful’ intersection — I mean meeting, but marketing jargon is addictive if you are an idiot — between Nordic and Japanese food.

It is a wealth mall from hell, then, in the style of Terminal 5’s main street. I had hoped pandemic would suppress such places — they sell snobbery, not food and they take up floor space that could go to better restaurants — but they are the Japanese knotweed of cities of wealth enablers. They always spring back to signal the health (I joke) of the nation.

You take a lift — or pale, smooth stairs — to the roof, on which there is bright pale restaurant and a terrace overlooking Belgravia’s chimneys. This room (they would call it a space because their souls have been ripped out by contemporary design magazines) would be fine — it is a glorious shell — if the aesthetic hadn’t collapsed into cashmere neutrals dash Valium dash divorce. I haven’t seen so much beige since I last stared at a Butterscotch Angel Delight and thought: I wish you were blue.

The terrace is designed by a Finnish horticulturalist — for this, I thank her — and the interior looks like a house-plant convention. It is a gathering place for the native rich: there are babies, there are dogs, each with their own cashmere neutrals and consultant stylist. The core client is dressed exactly like the restaurant (or more likely, vice versa): so much so that I wonder why they don’t slap ‘Private Club’ on the frontage and leave the rest of us out of it. (‘If you aren’t dressed like a Butterscotch Angel Delight, GET OUT.’) The staff are either overworked, which is greedy, or they have sucked in the marketing lie that we should be grateful to eat in a restaurant the colour of Angel Delight that should be a library overlooking a Waitrose that is pretending not to be a Waitrose (I have never seen a Waitrose cower before). We did not feel loved. We did not even feel visible.

But we are doughty, and we order food which, being for people who do not like food, is ashes. The new potato in new potato, egg and malma cheese (£11) is a raw sliver, though it isn’t hard to boil a potato; the chicken in chicken, white asparagus and mushroom (£23) is skinless and tastes worse than boiled (and you can do such wonderful things to chicken with butter, garlic and tarragon); the aubergines, morels, wild garlic and barley (£21) is completely inedible — even for vegan food it is a food swamp; the sprouting broccoli with mustard and almonds isn’t burnt, it just tastes like it is. It looks beautiful in the Instagram style because, like the clientele, it exists to be looked at, and lovely though it is, it is not good enough for me.

Pudding — a design of chocolate, soy and skyr — is slightly better: it looks like a miniature Giant’s Causeway, but you can’t do much to ruin chocolate. We flee through a shop on a lower floor that sells clothing, knives, beauty products and, most weirdly, a bicycle. Here the victory over taste by bad design is complete. I suppose it is a sign of survival, though that feels too kind: bad restaurants are back.