Pule cheese or magareći sir is a Serbian cheese made from the milk of Balkan donkey. A characteristic feature of Serbian cuisine, Pule is not only extremely rare but also the most expensive cheese in the world.
Zasavica donkey reserve, a donkey farm inside Zasavica, about 80 kilometres from Belgrade produces the donkey cheese by hand-milking a herd of about 100 endangered Balkan donkeys. By selling the donkey cheese at 1,000 pounds per kilogram (app. $576 a pound), the Zasavica donkey reserve plans to sponsor their conservation work.
It takes 25 litres of donkey milk to produce just one kilogram of white & crumbly smoked cheese. Currently, the cheese is made only on advanced order basis but farm exports are expected soon in the United Kingdom, Germany and the rest of the world.