This question gets asked here pretty often -- not discouraging new comments, but here are some older threads on the topic (sorry for the naked hyperlinks, but new/old Reddit formatting seems to be weird):

https://www.reddit.com/r/AskHistorians/comments/6z42la/what_was_the_italian_cuisine_before_the_tomato/

https://www.reddit.com/r/AskHistorians/comments/2fcqkd/how_did_the_tomato_come_to_be_such_an_integral/

https://www.reddit.com/r/AskHistorians/comments/2r4ghl/what_was_italian_food_like_in_the_14th_and_15th/

https://www.reddit.com/r/AskHistorians/comments/1bmd2y/when_did_traditional_italian_cuisine_start_and/