By: Halacha Yomit team of OU KOSHER
Is one permitted to take a challah from the freezer on the first day of Yom Tov, so that it will be defrosted in time for the nighttime meal?
In general, there is a prohibition to prepare on Yom Tov for after Yom Tov, or from the first day of Yom Tov to the next, even if the preparation does not involve any of the melachot (39 forbidden activities). This restriction is known as hachanah. For example, one is not permitted to wash dishes on the first day of Yom Tov, if one will not need those dishes until the evening, when the second day of Yom Tov has begun.
However, Rav Belsky, zt”l, ruled that one may defrost challah or meat so that it can be used at night. This is because the removal of the challah from the freezer does not immediately prepare the food for the next day. For many hours the bread will remain frozen, and the thawing happens on its own. Since one does not actively thaw the food, but rather it defrosts on its own, this is not a prohibited form of hachanah.