Who could not eat for three hours because food was added to the pot all the time?

The case was in Hong Kong, he hired there to help a street soup merchant. The merchant had a cart with a boiler, soup was cooked right here, on the street. He says their cart has been in business for over half a century, and the main secret of the soup business was to never wash the boiler. They cooked the soup all the time, without the slightest break. In fact, they sold the same fish soup for fifty years in a row, the same and not the same, because they were constantly adding some new ingredients, the ones they were able to get.