Bennett said the decision to put the dish - a popular street food in the Philippines - on the menu came after requests from diners, mainly Filipino men.
Filipino Louis Cruz, a dairy worker, who often ate the dish back home, believes in the "power" of the soup.
"The power from that part of the bull that we consume is being passed on to us, we believe," Cruz said.
"This is our secret weapon, and that is why Filipinos don't need Viagra."
Cruz described its texture as "chewy, gummy and spongy" and said it tasted very much like "soft tender cartilage".
Legend has it that the soup got its name because restaurants did not want to label its explicit ingredient.
They would list on their menu four types of soups - chicken, pork, beef and seafood - and an option "5" to lessen the shock factor.
Ingredients used in the soup include the bull penis, testicles and other organs such as lungs and liver, with a mix of Chinese herbs.
Preparation involves up to eight hours of boiling, and the meat being chopped into bite-sized pieces.
According to Bennett, it is mainly the testicles that give the broth its creamy, oily texture.
Massey University sociologist, Professor Paul Spoonley, said when it came to the local market, it would take a "brave or adventurous" diner to try such a dish.
"There are European equivalents, black pudding, kidneys or liver, but these are not part of the experiences of New Zealanders," Spoonley said.
But he said the size of Asian communities now gave restaurants the confidence to serve food that appealed to immigrant food memories.
"Some restaurants don't see the need to adapt for local tastes.
"There is a market that has increased in size and which now generates its own demand," he said.
