Biscotti
The confusion on the name may have been born from the fact that on the old sign (still present) of "Biscottificio Antonio Mattei," the leading manufacturer of biscuits of Prato, is written just below the name of the shop: "Manufacturers of cantuccini," which at the time were one of the major products of the biscuits. The sign has remained unchanged, and after such a long time people are accustomed to associate the name "cantuccini" with the biscuits typical of Sardinia and Sicily.