Bacalao al pil pil is a Bilbao invention: salt cod slow-cooked in olive oil with garlic and dried chili, then emulsified by shaking the pan until the gelatin and oil form a thick yellow sauce that coats each piece.
Where to eat it: 7 restaurants across 2 cities.
Bacalao al pil pil traces to mid-19th-century Bilbao, when merchant Simon Gurtubay over-ordered salt cod from Norway in 1836. Forced to sell the surplus, Bilbao kitchens developed the slow-emulsified sauce technique that made the dish a city staple. The pil pil name imitates the bubbling sound of the slow simmer. Casa Rufo, La Despensa de Etxanobe and Mina all run versions; the deep-yellow emulsion is the test, as the gelatin from the cod skin must bind with the oil into a thick sauce without breaking.
Common allergens: Fish
Tip from the editors. If the sauce does not emulsify, strain off most of the oil and whisk a tablespoon back in at a time, working from a small base.
Casa Rufo on Hurtado de Amezaga in Bilbao since 1955 grills the canonical Bilbao txuleta over open flame, between deli counter and dining room.
Signature: Txuleta, Bacalao al pil pil, Pimientos del piquillo
Order: The txuleta from the grill; the bacalao al pil pil as the starter.
Tip: Lunch 13:30-16:00, dinner 20:30-23:00; closed Sundays. The deli counter is worth a look.
La Despensa in Bilbao is Etxanobe's Michelin-Guide bistro side beside the Atelier, with a Bilbao tasting menu and traditional Basque a la carte plates.
Mina has held one Michelin star since 2013 for Alvaro Garrido's modern-Basque tasting menu, now a 25-cover Indautxu room on Calle Ercilla. Family-friendly.
Bar Charly on Plaza Nueva in Bilbao since 1973 keeps a traditional Casco Viejo pintxo counter with bacalao croquettes, bonito and the gilda.
Try: Pintxo gilda, bacalao croquette
Casa Vergara on Calle Mayor in San Sebastian's Old Town since 1948 turns out the bacalao al pil pil pintxo for under 4 euros, the canonical budget bite.
Try: Bacalao al pil pil pintxo with a glass of Txakoli
Tip: Terrace fills first; the pintxo plus Txakoli is under 6 euros.
Casa Urola on Fermin Calbeton in San Sebastian's Old Town keeps one of the most complete Basque wine lists in the Old Town, with Txakoli on tap and a deep.
Signature pour: Itsasmendi Txakoli by the glass
Wine focus: Basque Txakoli, Rioja Alavesa and growers
Food: Pintxos counter and full dining room upstairs
Tip: Drink Txakoli at the counter; the dining room upstairs lets you settle in with a half-bottle of Rioja.
Bodegon Alejandro on Fermin Calbeton in San Sebastian is the underground Old Town room where Martin Berasategui won his first Michelin star in 1986.
Signature: Merluza a la donostiarra, Txuleta, Tarta de queso
Order: The merluza a la donostiarra in cazuela and the txuleta from the grill; finish with the burnt-top cheesecake.
Tip: Book the 14:00 lunch slot for the calmer service. The staircase entry is easy to miss; the door is set below street level.
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