In addition, it is sometimes used more generally to mean "what's happening," even when no food is being prepared.
It is sometimes preceded by the rhyming phrase, "Hey, good-looking..."
I don't recommend you use it this way, as it's a little silly, and a non-native speaker might not have the fluency to use it ironically. You may see it in this context, however, which is why I brought it up.
In AmE generally used to inquire about what is happening (in your life, at the moment etc.). In popular usage, more recently replaced by "What's up" which does not necessarily require an answer and can be/is used more as a greeting than as an actual inquiry.