While the signature vegetable of Sicily is the eggplant (especially the smallish white ones), the signature dish, I have read several places (although I’ve also seen it ignored), is peperonata. Peperonata is sauteed sliced peppers (various colors) stewed with onions and tomatoes, a few green olives, and flavored with basil and red wine vinegar (salt and pepper, too, of course). Well, that’s one version.
Vegetable stews that are heavy on tomatoes, onions and peppers are big all around the Mediterranean. Add eggplant and you’re headed toward puttanesca or caponata….