ou are hungry, wandering the streets of the old city. Something about the stone building draws you in. There’s an iron sign with a lot of k’s and z’s. The antique oak door is slightly ajar, and when you peek inside from the sidewalk, things appear promising: The tables are full of jolly-looking people speaking in Euskara, the ancestral Basque language, while in the open kitchen at the back, two cooks in white aprons are hoisting extra-large txangurros, or spider crabs, into a pot. You notice that many (or most) of the diners are past retirement age and that most (or all) of them are men, but you’re intrigued and move in closer. Did the six guys at a far table just burst into a folk song while refilling one another’s glasses with txakoli, the local white wine? They did.