Perpetual stew
From Dragon Eye Atlas
A perpetual stew, also called "forever soup" or "hunter's pot" is a stew that is kept over the fire constantly, with its ingredients replenished with whatever is available over time. While the ingredients change over time, the pot never goes empty and is always kept hot. By staying hot, the contents never spoil and an individual piece of meat or vegetable can stay in the pot for years without going bad.
This kind of stew is very common in inns around the world, especially in the Elladan, Tallian and Luari cultures.
For the inn keeper it has the advantage of being easy to make and keep as he can use whatever ingredients he can get cheaply. For the guests it has the advantage that a hot stew can be on your table within minutes of coming through the door, something especially welcome in the winter. It is also said that the blending of ingredients in the pot creates a unique and interesting taste.
Communal Stew
A variation of the perpetual stew is the communal stew, where instead of paying for a meal, guests are expected to contribute something into the stew. A traveller might bring a rabbit he hunted, add it to the stew and take out one or two plates for himself. A farmer might contribute some vegetables, the local baker a loaf of bread, etc.
Communal stews are often found in small settlements such as logging camps where a central kitchen serves as the local gathering place.
Note: The concept of the perpetual stew is based on actual medieval history - see https://en.wikipedia.org/wiki/Perpetual_stew