It's past opening time at Goiz Argi but the shutters are still down. Advertised trading times for San Sebastian's famous pintxo bars, the Basque equivalent of a tapas joint, are to be taken with a pinch of salt. But with so many of them dotted around the streets of the old town, there's no danger of going hungry. Our guide, Englishman Jon Warren, of tour company San Sebastian Food, ducks under the metal grill and gets the owner to open up.
Warren gave up his career in London's finance sector and moved to San Sebastian after experiencing the quality of the gastronomy during a one-night stopover back in 2002. Established in 2009, San Sebastian Food grew out of Warren's habit of giving dining tips to guests while working at Villa Soro hotel in the city. And with half of Spain's three-Michelin starred restaurants and dozens of high-class pintxo bars in the city, he wasn't short of a recommendation or two.
Almost as soon as the shutters are pulled up, the bar fills with hungry diners. On Warren's advice we eschew the platters of potato tortilla, morcilla (black pudding made with rice) and txangurro (spider crab tartlets) laid out at the crowded bar and instead choose from the cooked-to-order "pintxo caliente" menu on which the real house specialities are to be found.
Pintxo is Basque for "spike", and many dishes are served on toothpick-sized wooden skewers. The plancha grill sizzles with the best-selling brocheta de gambas. This classic pintxo presents griddled prawns with a delicious sweet and sour garlic, red, green pepper and onion vinaigrette, served on a slice of crunchy baguette. We wolf them down, discarding our paper napkins and skewers on the floor in the accepted manner, doing our bit to keep the limited bar space clear of the quickly mounting detritus. Our bill is totted up based on what we say we've had to eat and drink and what the barman can recall serving us. Mistakes are bound to be made, but with most plates costing just two or three euros, it all evens up over the course of an evening.
We rejoin the crowds wandering the flagstoned Calle de Fermí* Calbetó* that's home to a number of highly rated bars. It's before 7pm and we've started our bar crawl early in order to avoid the real crush later in the evening.
In a little over two hours we hit half a dozen more places. We sample plump tigres – Galician mussels in a light tomato sauce, and mayonnaise – and salsa-drenched patas bravas at Mejillonera. At Gandarias, the Solomillo (rare sirloin steak and baked green pepper with a liberal sprinkling of rock salt on bread) is simple and stunning; and I could live on the Carrillera de Ternera – slow cooked ox cheek with chickpea and parsley vinaigrette – at La Cuchara de San Telmo. Each bar has something it does well and with Warren's insider knowledge we find it every time.
A similar degree of gastronomic connoisseurship is on show at the La Brexta fish market where our guide is chef Alex Barcenilla, of Ziaboga restaurant. Each stall holder tries to out-do the next with beautifully arranged displays. At one, the fish is so dazzlingly fresh that it seems to leap from the slab.
Barcenilla points out some monkfish with bellies slashed to expose their black innards, a sign that the fish will be tender. We buy some goosefoot barnacles, costing more than €100 (£80) a kilo, the price a reflection of the perilous method of harvesting them from Galacian cliffs. We take them back to the restaurant where they'll form part of a very long, lazy lunch overlooking the Bay of Pasajes. But first we have to help prepare it.
In the kitchens of Ziaboga, Alex shows me how to prepare the classic Basque dish of merluza en salsa verde (hake in green sauce). Under his guidance, I finely chop some garlic, then flour a thinly cut steak of the meaty white fish. I fry it in olive oil, add the garlic, then white wine which, thickened by the flour creates a sauce that I finish with a generous pinch of chopped parsley.
Lunch proper begins with more hake, this time the chins, a much prized part of the fish that fetched over €50 a kilo in the market. They're served three ways: sautéed, pan fried in flour, and pil pil – slow cooked in olive oil to release their natural gelatin, which creates a thick sauce that bubbles in the pan making a "pil pil" sound.
Although Alex now cooks mostly traditional northern Spanish seafood dishes, he trained with Pedro Subijana, one of the leading lights of the new Basque cuisine movement of the 1970s. And its to Subijana's three Michelin star Akelarre, a 15-minute drive from the city centre on the cliffs overlooking the Bay of Biscay, that we head for dinner.
During a specially laid-on demonstration in the restaurant's smart studio kitchen, we learn how to make something that looks just like carpaccio of beef from beetroot paper rolled between sheets of pasta. But Subijana has an even better trick up his sleeve. As a canapé, we're presented with a tray of hotel bathroom products and instructed to eat them. Fortunately, the liquid soap gel is tomato gel, the sponge is made of almond, the tub of hand lotion contains a local goat cheese and the purple mouthwash is champagne with pomegranate. It's a fitting start to a meal that's full of invention and surprising, delicious flavours.
There are many reasons to visit San Sebastian. A beautiful belle époque city arranged around the sandy, crescent shaped Playa de la Concha, you could come for the surfing, to shop at the upmarket boutiques, for the annual international film festival, or to take part in the Tamborrada, a 24-hour drumming festival held every January. Frankly I could take or leave all that – just show me the way to the next pintxo bar.
The nearest major Spanish airport to San Sebastian is Bilbao. Andy Lynes flew as a guest of Vueling (0906 754 7541; vueling.com). One-way flights from Heathrow to Bilbao start at £48. Bilbao is also served from Stansted and Manchester by easyJet (0843 104 5000; easyjet.com).
Biarritz, across the border in France, is slightly closer to San Sebastian, You can fly from Gatwick with easyJet (0843 104 5000; easyjet.com) or from Stansted and Manchester with Ryanair (0871 246 0000; ryanair.com).
Alternatively, sail from Portsmouth to Bilbao with Brittany Ferries (0871 244 0744; brittany-ferries.co.uk).
Andy Lynes stayed at Villa Soro, San Sebastian (00 34 943 29 79 70; villasoro.com), where doubles start at €165 (£131), including breakfast.
San Sebastian Food, Calle Aldamar 30 (00 34 943 421 143; sansebastianfood.com), offers Pinxtos Tours in San Sebastian from €85 (£68), and cookery lessons from €75.