Bread and a cooked food

Hi,

As we have already noted, the purpose of creating an Eruv Tavshilin is to permit cooking on a Friday Yom Tov for Shabbat, by beginning the cooking process before Yom Tov.

We try to set aside one cooked food and one baked food, since one may wish to either cook or bake for Shabbat on Yom Tov, and they are fundamentally different processes in the eyes of Jewish law. However, in practice, one who only set aside a cooked food may rely on that item for both cooking and baking.

(Code of Jewish Law Orach Chaim 527:2)

Have a great day,
Mordechai