This Spanish bocadillo sandwich variety uses a type of Spanish blood sausage called morcilla as a filling. The morcilla sausage can come in the form of a thick, paste-like spread (typical of León) or as thick sausage slices (with the most famous being the Burgos version) which have been fried, grilled, or roasted.

Rustic, Spanish-style baguette (barra de pan) is the most common type of bread used for this sandwich, although other types of Spanish bread may also be used. Traditionally, the baguette is cut in half along the middle, and it is then filled with the sausage.

Other typical additions to the sandwich’s filling include caramelized onions, fried eggs, potato fries, tomatoes, pisto (ratatouille), and tortilla. This sandwich is commonly enjoyed as a quick and simple meal for lunch or dinner, and it is often accompanied by a fresh green salad on the side.