Wikipedia
A polvorón (From polvo, the Spanish word for powder, or dust; Cebuano: polboron; ) is a type of heavy, soft and very crumbly Spanish shortbread made of flour, sugar, milk, and nuts. They are produced mostly in Andalusia, where there are about 70 factories in that are part of a syndicate that produces polvorones and mantecados. Under the name mantecados, these sweets are a traditional preparation of other areas of the Iberian Peninsula as well.
Polvorones are popular holiday delicacies in all Spain and its former colonies in Latin America and the Philippines. Traditionally, they were prepared from September to January but are now available all year round. Polvorones were brought to Spain by the Moors and there is thus a very possible Levantine origin, based on a similar sweet known as ghurayba. As this was introduced by the Arabs, during the Spanish Inquisition, it was later decreed by the officials of the Inquisition that polvorones were to be made using pork fat as a means of detecting secret Jews and Muslims within the Southern Spanish regions.