Sort:  

Is that a question you have an answer to or something you don't and are thinking I do?

I think fire for cooking might've been an accidental discovery.. what do you think?

Well fire is somewhat uncommon in nature but it does happen. Obviously it existed before humans started using it. At some point it was figured out how to do it, most likely from friction. It seems to me that once fire was figured out it was probably mostly used for self defense, then lighting dark areas then eventually to cook food.
I think the early use of fire for cooking was mostly used to make food that would otherwise not be eatable. Now days people cook almost everything and its not necessary or healthy for the most part.