Wikipedia
Lampredotto
Lampredotto is a typical Florentine dish, made from the fourth and final stomach of a cow, the abomasum.
"Lampredotto" is derived from the Italian word for lamprey eels, lampreda, as the tripe resembles a lamprey in shape and color.
A sandwich with lampredotto—panino al lampredotto has been described as a "classic Florentine" sandwich and is a traditional regional street food in Florence. Lampredotto is typically chopped, slow-cooked in a vegetable broth, seasoned with herbs, and served on a bread roll. It is often topped with a spicy sauce or a green sauce ( salsa verde).
The Daily Meal has called the lampredotto with "a tripe-lover's dream."