Opera Tavern, 23 Catherine Street, London WC2

To a much greater extent than is generally acknowledged, our eating habits are determined by economic cycles. I take there to be a causal relation, for example, between the prevailing austerity and a sudden proliferation of excellent tapas restaurants in London, most of which are packed as never before. The reasoning is simple: we go out to try new foods, and to eat things we wouldn't cook at home; so if we're cutting back on meals out, on those occasions we do venture out we'd rather six or seven small courses than three big ones. Comprende?

That said, not all of them are Spanish. Polpetto, on Soho's Dean Street, does magnificent tapas for really quite cheap prices, including an unbeatable soft-shell crab. Much of its menu is Venetian. Fino on Charlotte Street is very good, despite the discomfiting lack of natural light. And the charming Cambio de Tercio on Old Brompton Road in west London is probably the best Spanish restaurant in London, though last time I was there Prince Harry turned up with Guy Pelly and a phalanx of blondes, which caused me to choke on my manchego.

And two more superb restaurants, affordable and always busy, attest to this argument, combining Spanish and Italian influences along the way. One is Salt Yard, the kindest thing about Goodge Street in central London. The tables are crammed together, but the fabulously rustic menu is almost impossible to fault. A swordfish carpaccio with chicory marmalade, blood orange and walnuts (£7) is well sourced and handled, and the roasted scallops with cauliflower purée, hazelnuts and garlic (£9.70) is silky and hugely satisfying. Crisp hake with pepper aioli (5.50) and the confit of pork belly with rosemary-infused cannellini beans (£6.65) are other highlights. You can also get a generous selection of either Spanish or Italian charcuterie for £8.95.

So successful is this formula that owners Simon Mullins and Sanja Morris opened a similar venture called Dehesa in Ganton Street, closer to Piccadilly, in January 2008. And this year they have opened Opera Tavern in Covent Garden.

I'm celebrating my brother's marriage, so I feel obliged to try most of the menu on your behalf, and am spending more than you need to. A couple could eat very well here, have a bottle of wine, and leave with change from £80.

There is a strangely New York feel to the upstairs dining-room, overlooking London's thespery, with De Gournay wallpaper, pastel colours, and very 20th-century Italian artwork. Downstairs is rather different, with the heavy imprint of the Victorian pub designed by architect George Treacher more than discernible. The old beer cellar is the modern kitchen, and the snacking encouraged downstairs, with charcuterie on display, is at variance with the gorging under way upstairs.

Much of the menu is the same as at Salt Yard. The pork belly is again wonderful; a lamb leg with pumpkin gnocchi, super-salty anchovies and brown butter and mint (£6.50) is beautifully weighted; hot and crunchy courgette flowers stuffed with oozing, unrestrainable goat's cheese and drizzled with honey (£7.55) is another welcome refugee; a braised ox cheek with roast parsnips and purée, thyme, and pickled walnuts (£8) throbs with flavour; and the grilled, fatty, lurid Iberico presa (pork shoulder) is cleverly cut through with capers, shallots and lemon. It's hard, too, to see how £4.25 could be better spent on a night out in London than on these stunning grilled scallops, with pungent butternut-squash purée, shallots, truffle dressing, and – a winning addition – migas, or Spanish breadcrumbs. The marriage of textures brings out my own theatrical abilities, or lack thereof, and I order some more.

As mini-burgers go, the Iberico pork and foie gras burger, with melted manchego and caramelised red onion, is a snip at £5.50, even after the removal of tedious lettuce (rocket would have been better). The wine list is reasonable, and there is a broad range of cheeses at £4.25.

Executive chef Ben Tish and head chef Jamie Thickett seem to me not only talented cooks but perceptive business brains too. They have produced a menu that will satiate the luvvies of Drury Lane and tickle the fancy of recession refuseniks. And if Opera Tavern does as well as it ought, they will have provided further confirmation that in tough times, tasty tapas is a certain winner.

8.5/10

Scores: 1-3 stay home and cook, 4 needs help, 5 does the job, 6 flashes of promise, 7 good, 8 special, can't wait to go back, 9-10 as good as it gets

Opera Tavern, 23 Catherine Street, London WC2, tel: 020 7836 3680. Lunch and dinner, Mon-Sat; lunch, Sun. £150 for four, including three bottles of wine

More small wonders

El Rincon

Longworth Street, off St John's Street, Manchester, tel: 0161 839 8819

Off the beaten track, yet located in the centre of Manchester, this stalwart Deansgate tapas bar offers genuine Spanish buzz

El Gato Negro

1 Oldham Road, Sowerby Bridge, tel: 01422 823 070

A revelation – this tapas bar in a cheery former boozer is superb – though it's been difficult to get a table since its success on Gordon Ramsay's F Word

Café Ikon

Ikon Gallery, Oozells Square, Brindleyplace, Birmingham, tel: 0121 248 3226

Doing well under new management (if perhaps a bit chaotic), this stylish tapas bar makes for a funky find – especially in a city centre rather dominated by chains

Reviews extracted from 'Harden's London and UK Restaurant Guides 2011' www.hardens.com