A perpetual stew, also known as forever soup, hunter’s pot, or hunter’s stew, is a pot into which foodstuffs are placed and cooked, continuously. The pot is never or rarely emptied all the way, and ingredients and liquid are replenished as necessary. Such foods can continue cooking for decades or longer if properly maintained. The concept is often a common element in descriptions of medieval inns.
Foods prepared in a perpetual stew have been described as being flavorful due to the manner in which the ingredients blend together. Various ingredients can be used in a perpetual stew such as root vegetables, tubers (potatoes, yams, etc.), and various meats.
People have been doing this for hundreds of years without issue.
Hundreds of years, yes. Without issue? Definitely incorrect. It is a statistical certainty that, in the entire course of history, someone somewhere has gotten sick and died from this cooking method.
Pedantry aside, it’s all about who’s making the stew that matters. A seasoned chef today with the sufficient knowledge of modern food safety practices can keep a stew reliably safe to eat. Some old farmer centuries ago will experience a lot more opportunities for contamination and won’t notice until they get the shits.