Colatura di Alici
The sauce is a transparent, amber-colored liquid, produced by fermenting anchovies in brine. The fish used in the sauce are harvested from the Amalfi Coast between March 25 (Annunciation) and July 22 (Feast of Mary Magdalene).
The origins of colatura di alici date back to ancient Rome, where a similar sauce known as garum was widely used as a condiment. The recipe for garum was recovered by a group of Medieval monks, who would brine anchovies in wooden barrels every August, allowing the brine to drip away through the cracks of the barrels over the course of the process. Eventually the process spread across the region and was perfected by using wool sheets to filter the brine.