"This festival is all about fun, food and bravery," said Ljubomir Erovic, the Serbian chef and testicles gourmand specialist who organises the bizarre cooking festival and has published a testicle cookery book.
The bulls' testicles are the best, goulash style," said last year's winner Zoltan Levai, stirring a metal pot heated by a wood fire and filled with vegetables and large testicles that he said were provided from a state-run slaughter house.
The festival – which includes dishes like testicle pizza and testicles in béchamel sauce flavoured with a variety of herbs found in the region.
Visitors eat the dishes with plenty of wine or beer, and cool themselves in a small mountain river that flows beside the makeshift cooking stands blasting folk music. The stalls also sell roasted pig or lamb, "as a side dish".
"I came here last year, and decided to come back," said Anna Wexler, an Israeli citizen originally from New York who's now a member of the festival's jury. "It was delicious. There was testicle moussaka, goulash, stallion, boar, bull and many other things."
The festival also gives prizes to to those who have made the news for being "ballsy". This year one of the unsuspecting winners is Barack Obama.
"He's the bravest man in the world," said Mr Erovic. "Obama took over the world at the most difficult economic and political times," Erovic said. "He showed he has balls."
The other prize went to American pilot Chesley "Sully" Sullenberger who last year glided a passenger jet into the Hudson river in New York rather than risk crashing in a densely populated area trying to reach an airport.