Delicious croc tails

I fully expected to dislike Seraphin intensely. The whole set-up filled me with a sense of foreboding. For one thing, it's on that stretch of Upper Street that, apart from the antiquey bits, reminds me of a gigantic hen party: all white high heels, bare legs and indifferent chain bars. And it's not wildly prepossessing from the outside, a former branch of Dome that looks like it's been given little more than a lick of black gloss. In fact, the interior is rather sombrely striking.

But it's the menu that really gave me a case of the glooms. It comes over as a misguided experiment from a tyro chef who's been let loose in a kitchen he mistook for a chemistry set. How about these babies: pan-fried breast of pigeon, puree chickpea risotto, ribbons of chorizo and cherry vinegar dressing? Or wild ostrich fillet with curryglazed spinach, coconut shavings, pan-fried salsify, sweet potato purèe and fig sauce? Even soup comes with Parmesan and caviar sorbet.

Not only are the dishes alarming, but prices are decidedly ambitious. At around £8 for starters and up to £21.50 for mains, they really needed to be able to pull it off.

But sorry schadenfreude fans, this isn't going to be a hatchet job. We deliberately went for the most esoteric choices on the menu. And ended up rather liking them.

Brie mousse - a solid pate, rather - came sandwiched between Parmesan crisps and topped with frisee. Keeping it company were caramelised red endive, blood orange and a Grand Marnier reduction. It all, weirdly, hung together. But this was a wallflower compared with our other starter: lobster medallions interspersed with waxy, lime-marinated potatoes, topped with a 'garlic bonbon' (a slowroasted whole clove), 'almond rose' (like non-roasted, honey-roast almonds) and lobster jus. It was a concoction that defied culinary wisdom and logic but was, erm, quite nice really.

Main courses were even further out there, like my fillet of halibut with lobster Puy lentils, white asparagus, cipoline onions and a lemongrass veloute. This confounded all expectations by actually being excellent, a glorious slab of perfectly cooked fish, punchily flavoured lentils, fragrant vegetables and a scented, rich, buttery sauce.

But the crowning moment came with a dish containing confit pork belly, black tiger prawns, tapenade, Jerusalem artichokes in lime and tarragon and orange segments. Oh, and crocodile tail. To go with this, we were given a sauceboat. 'It's fishy sauce,' our intrusively helpful waitress explained. It turned out to be made from white chocolate.

Revolting, obviously? Well, no: the pork was splendid, as were the prawns - and the sauce was surprisingly harmonious. If some components had been ditched, this could have been quite a remarkable piece of cooking.

So who's responsible for this febrile creativity? One Robson Guerra, a perfectly charming Brazilian chap, late of Claridge's. 'It's all my own invention,' he declares proudly of his menu.

On the evening we visited, he was tinkering with ice creams, just completing a batch of pancetta flavour. Yep, Italian bacon. It was astonishingly gorgeous: ridiculously rich, sweet, smoky, frozen lard, like a Glaswegian's wet dream. We also had a subtle and divine avocado and chilli, and a more conventional roasted oat and whiskey.