http://revach.net/article.php?id=1046

Section: Halacha   Category: Tshuvos
Shabbos Yom Kippur: Do You Make Kiddush, Eat Lechem Mishna, Say Ritzei?

There is a machlokes rishonim as to how we view eating on Yom Kippur. Some say once you are permitted to eat it becomes like a regular Yom Tov meal, especially if it falls on Shabbos.  Other hold that since it is forbidden to eat, when sick people and children do so it does not take on Yom Tov/Shabbos status. The consensus of the Mishna Berura (618:10) and most poskim is that l'halacha one should be machmir when possible. Therefore;

1. Yaaleh V'Yavo (Mogen Avrohom) and Retzei should be said since it is not considered a hefsek. If one forgets to say it they should not go back and bench again.
2. Kiddush should not be made since it can be Bracha L'Vatala (Rebbi Akiva Eiger disagrees).
3. According to the Piskei Teshuvos, Lechem Mishna should be used whenever possible, since there are varying opnions one should be machmir here as well.

Important Note: We bring this tshuvah as a starting point for discussion and not to convey any halacha. We try to convey the Tshuva to the best of our ability. We admit that our understanding may not be accurate. One should learn the tshuva to verify the accuracy of our interpretation. Please understand that this Tshuva may not be the final word on this topic. One should consult a Rav before drawing any conclusions.