Costrada de Aoiz Food and drink · Aoiz/Agoitz, Prepirineo, Navarra Image of Aoiz/Agoitz, not of the place itself. The costrada is Aoiz's typical sweet, a three-layer puff-pastry cake filled with pastry cream, whose golden, crunchy surface (costra, "crust") gives it its name. Born as a way of using up pig lard after the traditional pig slaughter, it was traditionally prepared for major family and religious celebrations; today it is only made by hand in Aoiz, which has its own gastronomic brotherhood dedicated to it. Photo: SamHolt6 (CC0) What to see and do in Aoiz/Agoitz