'My first course is as thuggishly rich as Eric Cowell's dad'
Occasionally I'm moved smugly to suspect that I've seen it all. And then something keels up to remind me that I ain't seen nothing yet. This new arrival, tacked on to Borough Market, appears to offer something genuinely, perhaps barkingly, new. The Hotel Chocolat company tells us that Rabot 1745 is "Britain's first gourmet chocolate restaurant" specialising in "cocoa cuisine". They tell us this in the kind of breathless tone of voice that suggests it's what we've all been waiting for, much in the way we've all been waiting for Britain's first restaurant staffed by chimpanzees.
This is a curious fish altogether. Heavy on the "hurricane-felled ironwood", it's supposed to come across like a Caribbean plantation house. It's more like eating in a Kelly Hoppen-designed sauna. There are winged wooden chairs, polished wooden tables, wood-panelling, walls padded in what looks like chocolate-covered leather, decorative cocoa bean-shaped hangings… It's overwhelmingly brown. We get it, guys. And despite the fact that they roast beans on site from their own St Lucia estate – hence the name – there is none of the seductive fug you'd expect from a joint whose ground floor is an actual chocolate factory.
The outrageously garrulous menu – why use one word when "rare, seared beef fillet infused with Borough-roasted cacao, celeriac, cornichon and juniper condiment, cacao gin jelly, cacao balsamic syrup" will do? – hammers home the message. It's not about sweet chocolate until you get to pudding, but rather cocoa bean, nib, rare white cocoa pulp. There are beans at our place settings: "Ecuadorean, Madam, freshly roasted this morning," beams our affable Scouse server. We rustle off the papery outer cover and bite in: the roasted nibs snap, nutty and buttery, cool then warm. Rich, dark flavour floods the palate. It's a cute touch.
But then we meet cocoa nibs in everything from soft-boiled eggs and salsify to focaccia, and the cuteness starts to get very old. You can have them crusting Scotch eggs (or "nib-crusted quail's egg pearl barley 'scotch egg' with warm salad of roasted vegetables, goats cheese and cacao oil emulsion", as the menu has it). Or with "sea tartare", or on buttered spinach; as curried nib oil or on in crackers with clam chowder. It arrives as a crumble with my blobby, spookily suave butternut dumplings, a messy assembly dotted with almonds and suffocated by creamy butternut puree. Here, too, are wilted, garlicky greens, roast potatoes and eldritch items that look like witchetty grubs: they turn out to be Chinese artichokes, or crosnes, thick with brown butter. It's a starter. The whole thing is as thuggishly rich as Eric Cowell's dad.
Presentation is as overwrought as the concept, a mulitiplicity of swoops and swirls and little jugs. With guinea fowl (overcooked and dry; thank goodness for the "nib-infused organic milk yoghurt") comes a disembodied poultry limb standing to attention like a guardsman. I've ordered slow-roast shoulder of Herdwick lamb, and the meat – already sticky, almost jammy, with a jug of even stickier "cacao balsamic" gravy that congeals as it pools out of its jug – is served with roast garlic mash out of which sprout batons of carrot and parsnip. The effect is as if Desperate Dan has gone modernist and deconstructed his cow pie.
Everyone around us is loving the place, and the pal I go with is happy as a cocoa nib-crusted clam. There's a ludicrous, tiered "chocolate Genesis" dessert – drinks, pralines, sorbets, truffles, what have you – that could keep a theobromine addict buzzing for hours. But despite the quality of the chocolate, the cumulative effect on me is a bilious one: I'm as queasy as if I'd necked a family-sized Galaxy selection box. It's inspired of them to have opened in Borough, not because it reflects their shared principles of seasonality and sustainability and slow foodery, but because it's full of tourists.
• Rabot 1745 2-4 Bedale Street, Borough Market, London SE1, 020-7378 8226. Open all week, lunch noon-2.30pm (11am-3pm Sun); dinner 6-10.30pm (10pm Mon-Wed). Three-course meal, about £35-40 a head, plus drinks and service.
Food 4/10
Atmosphere 5/10
Value for money 4/10
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