Does Dim Sum Duck live up to the hype? TOM PARKER BOWLES reviews the walk-in-only Cantonese hit in central London

I must have tried three times, maybe even four, queuing solemnly outside the tiny restaurant with the sky-blue signage and aquamarine façade. The reviews were universally rapturous, the prices refreshingly low. But Dim Sum Duck, tucked away on a King’s Cross side street, does not take bookings. And I’m not sure anything, even the most silken and slithery of cheung fun or historic har gau, is really worth an hour’s wait. I have the patience of a bluebottle at the best of times. And when it comes to lunch, it’s straight in or move on.

But then they opened another place, bigger this time, just around the corner on Pentonville Road. It’s still rammed, of course, just after the lunchtime peak, but there’s a table for me and my son Freddy (who takes his dim sum very seriously indeed) – and within moments we’ve ordered from the laminated, sporadically illustrated menu, very much a greatest hits of Cantonese classics. Don’t come expecting linen napkins, voluminous wine lists or siu mai gilded with gold leaf. Plates and bowls are plastic, service swift but smiling. This is all about the food.

Cheung fun: ‘a joyous contrast of the soft and crunchy’

Xiao long bao first, filled with pork and seething broth, the dough just thick enough to contain the liquid without splitting, but not so sullenly dense that chewing becomes a chore. Freddy slurps cautiously, then nods his approval. ‘Up there with Din Tai Fung and Min Jiang.’ High praise. Har gau are large and generously stuffed, the pert prawns pressed hard against the most thin and delicate of casings. Cheung fun, sheets of sublimely slippery rice noodle, are rolled and stuffed with prawns and crisp bean curd skin, so there’s that joyous contrast of the soft and crunchy. This is peerless dim sum, precisely made and precisely steamed, with no unnecessary frills or flourishes. As Freddy would have it, ‘peak’.

They do wonderful things with good seafood too, as is the Cantonese way. King prawns, expertly cooked so the flesh is still firm, buried under a blizzard of deep-fried chilli and garlic. You eat the whole body, shell and all, a thrilling cacophony of taste and texture. Razor clams, softly chewy, are engulfed in a mess of fresh chillies and vermicelli noodles. Then congee – bland, soothing and gently peppery – with minced pork, preserved egg, pickled vegetables and fried knuckles of dough. Pure exalted Cantonese comfort. Just like Dim Sum Duck.

About £35 a head. Dim Sum Duck, 186 Pentonville Road, London N1; dimsumduck.com