Prohoc noodles are known among Saigonese as num-bo-choc noodles or simply referred to as Cambodian fish noodles.
The dish first made its appearance in Saigon in the 1970s, with a small shop in Le Hong Phong Market in District 10 being one of the first places to sell it.
Ngo Van Hoa, 63, said the shop was opened by his father. “Two years after he returned to Vietnam from Cambodia, in 1972, our family’s life started to become more stable thanks to the business. My grandparents, my mother, Tu Xe, and now me, the third generation, have taken care of the restaurant.”
In full: https://e.vnexpress.net/news/travel/food/for-47-years-cambodian-speciality-remains-popular-with-saigon-foodies-3916839.html