Alfajores are sandwich cookies filled with dulce de leche, a creamy caramel confection made from milk and sugar. Alfajores have their origins in the Middle East. The Spaniards acquired their alfajor habit from the Moors, and brought it to South America, where alfajores have become an institution. There are restaurant chains dedicated entirely to the alfajor cookie, whose brand names are as recognizable and ubiquitous as Starbucks in the US. (La Casa del Alfajor in Peru and Havanna in Argentina are famous examples, but there are many more).
The typical alfajor is made with two slightly sweet shortbread-like cookies. Dulce de leche is the most common filling. There are many variations on this standard - nuts, fruits, and chocolate are popular additions. True alfajor aficionados prefer to eat the cookies a day or two after they are made, when the cookies have softened and melded with the filling.Alfajores - Only the Best Will Do