Is mutar during Shabbat turn on an oven through a clock, in order to have it already at coock temperature after motsae Shabbat? Can I use this oven after motsae shabbat?
It is permitted to set a shabbos clock to turn an oven on towards the end of shabbos in order that it be ready for baked right after shabbos. The reason is because you didn’t do any melacha on shabbos, what you did was before shabbos, and on shabbos it was the shabbos clock that turned it on. Just to be clear if there would be food in the oven when it turns on, then the halacha would be different.