⁃ In order to bake and cook on Yom tov for Shabbos, an Eruv tavshilin must be made.
⁃ It should consist of something baked like a full matza AND a cooked food (many use a hard boiled egg).
⁃ Take the matza and cooked item in your hand and make the Bracha (found in most siddurim before Friday night davening) and then put them away where they won’t get eaten until Shabbos.
⁃ It’s better for the food of the Eruv Tavshilin to be cooked on Erev Yom tov and not before.
⁃ If the food (egg) gets eaten or becomes inedible before the cooking is done then it can no longer be relied upon to cook for Shabbos.
⁃ If the baked food gets eaten etc. you can still cook for Shabbos.
⁃ It’s better for the food to be fully cooked well before Shabbos. However as long as it’s cooked before sunset it’s allowed.
⁃ The bread should be used for lechem mishna on Shabbos and eaten for Seuda shlishis.
⁃ All members of a household, including guests who are sleeping over, can rely on one Eruv Tavshilin.
⁃ If you don’t plan on cooking for Shabbos, make an Eruv without a Bracha.
⁃ If you only plan on lighting Shabbos candles, make an Eruv without a Bracha.
