Bustrengo is a traditional fruit cake originating from San Marino, although it is also popular in Bologna. It consists of cornmeal, flour, stale bread or breadcrumbs, eggs, olive oil, milk, honey, apples, figs, raisins, and zest of oranges and lemons.

Bustrengo is prepared throughout the year, but it is especially popular during the festive Christmas period. Traditionally, the cake was prepared in a fireplace, in a copper pot with a lid that was covered with hot coals. Due to the fact that bustrengo is very rich and dense, it is typically served in small portions, ideally with a shot of sweet wine on the side.