Potatoes Added to Cholent before Shabbos

Ingredients Added to Cholent close to Shabbos

One may not place a pot of food on the fire on Friday to be cooked on Shabbos, unless the pot is placed on a blech (a metal sheet covering the flame and the knobs) due to the concern that one may turn up the flame on Shabbos. (Another option is to add a piece of raw meat to the pot right before shkiah [sunset], but the details of that are beyond the scope of this article.) A cholent, or any other food, that is totally cooked (according to the basic halachah, even if half-cooked) before the onset of Shabbos may be left on an open fire, and a blech is not required. (Of course, if there is no blech, one may not put the pot back on the fire on Shabbos once it has been taken off.) 

What is the halachah if one finds out close to Shabbos that they will have additional guests for the Shabbos day seudah (meal), and they wish to add more potatoes and/or other ingredients to the cholent? If the newly added items will not be at least halfway cooked by shkiah, the cholent must be placed on a blech. In the event that the ingredients added to the cholent were not at least cooked up to a third of cooking, and the cholent was not placed on a blech before Shabbos, not only may the added food not be eaten on Shabbos, but the entire cholent becomes assur (forbidden), and none of it may be eaten until after Shabbos. Even after Shabbos, the cholent only becomes permissible after waiting bi’chdei she’yaasu (the amount of time it would take to cook it starting from after Shabbos).

However, the halachah is different if only water was added: If one adds water to soup or cholent before Shabbos, the water has to be warmed halfway before shkiah, or the pot must be placed on a blech. According to some, this is somewhat more than the temperature of yad soledes bo (temperature that would cause one’s hand to instinctively recoil). If the water did not reach the temperature of yad soledes bo before Shabbos and the pot was not placed on a blech—or if a non-Jew added water to a hot water urn on Shabbos (a common practice in some hotels, which is a problem halachically)—despite the fact that these actions are not permissible, one may drink the water from the urn and eat the soup and the cholent on Shabbos. This is because the added water becomes indistinguishable from the water that was there previously, and becomes botel (nullified) to that water.  #339

https://halacha2go.com?number=339

Practical Halacha: One minute a day. By Horav Yosef Yeshaya Braun, shlita, Mara D'asra and member of the Badatz of Crown Heights.