Dehesa, 25 Ganton Street, London W1

What this country needs is a good brunch. We don't dine at 1pm on the dot any more, or work our way through three formal courses. But for some reason brunch is seen as anti-British, destroying tradition with its leisurely style and informal timing, even though the term was coined in this country in 1895 by Hunter's Weekly, calling for "a new meal, served around noon that starts with tea or coffee, marmalade and other breakfast fixtures before moving along to heavier fare".

We don't trust brunch, being suspicious of anything that comes with its own lifestyle – but it's coming anyway. One sure sign is the weekend brunch at hot new Spanish-Italian diner Dehesa, just off London's Carnaby Street. It's the second restaurant from Simon Mullins and Sanja Morris of Salt Yard, with the same happy mix of Spanish tapas and Italian charcuterie.

The sleek black awnings, copper-fronted bar, high bench tables and tall, leather-cushioned stools scream cosy, cosmopolitan New York ethno-diner, while a curve of wooden counter holds legs of prosciutto and jamó*, salami and cured meats.

At night, the joint is jumping – and with no bookings, queues start to form to rival Frith Street's Barrafina. The menu lists meat, fish and vegetable tapas, including Salt Yard favourites deep-fried courgette flowers with cheese and honey, and confit pork belly with cannellini beans. I like the glossy, sweetly nutty slices of Norcia prosciutto, properly cut to order off the bone (£8), and the fragrant truffled Italian salami (£8). Top ingredients are served straight-up and simple, such as a goodly pile of crisp-yet-fleshy girolles on toast (£7.75) and a rustic bake of swiss chard, tomato sauce and poached egg (£4.95). The Spanish/Italian wine list goes hand-in-hand with the food, from a pale but balanced 2006 Hofstatter pinot nero Meczan from the Alto Adige (£30) to the 1975 Biondi Santi Brunello (£350).

My real mission, however, is brunch, and I'm hoping against hope for the Bloody Mary-fuelled buzz of New York's Prune or Sydney's Sopra. It's not to be }– at 1pm on Saturday, I'm the first in the door. But chef Ben Tish's menu puts me at ease, with its churros and hot chocolate, Padró* peppers, and char-grilled Tuscan sausages, and I get to sprawl in one of the two cute window booths with the papers.

Brunch is such a personal thing. For me, it means dipping in and out of a number of dishes rather than pigging out on one big fry-up, so I cover the table with these: a sweet, gooey, Spanish creamed rice with plums and a wild chestnut honey that is in itself finger-licking good (£4.75); pan con tomate with Serrano ham (£5.75), the suitably robust bread heavy on grill marks but too light on splodges of tomato; and a Bloody Mary (£7.50) that is such a belt of vodka, chilli, Big Tom and grain mustard that I kick myself for not having a hangover to cure. There is also a nicely browned tortilla (£6.50) built with sliced potato, sweet onions and Ibérico ham, which is good, if heavier, than the Barrafina beauty; and toasted sourdough with scrambled duck egg and morcilla blood sausage with mint (£6), that looks ordinary but tastes great. The coffee definitely needs work.

Fellow brunchers straggle in: a group of Spaniards seek the flavours of home, a lone shopper puts up with pancetta instead of bacon for his fry-up, and a group of six all have the hit dish – roasted foie gras with fried eggs and patatas fritas (£8.25).

Dehesa is a classy little place that swells the ranks of casual, produce-led Spanish-influenced diners such as Barrafina, Moro and Tapas Brindisa. Likeable and easy-going, it makes the produce the star, supported by personable service and usable wine options. At this stage, it's better at night than at brunch, but I think that says more about us than them.

14/20

Scores: 1-9 stay home and cook, 10-11 needs help, 12 ok, 13 pleasant enough, 14 good, 15 very good, 16 capable of greatness, 17 special, can't wait to go back, 18 highly honourable, 19 unique and memorable, 20 as good as it gets

Dehesa, 25 Ganton Street, London W1, tel: 020 7494 4170 (no bookings). Lunch, Mon-Fri; dinner daily; brunch, Thurs-Sun. Around £75 for dinner for two with wine and service; around £40 for brunch

Second helpings: More weekend wonders

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Giraffe

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