Crusty bread, tomatoes, basil, and vinaigrette are constants here, and then there are the variables: a bit of chopped red onion and white beans (both of which I add here) or cucumbers or fresh mozzarella, which is my favorite thing to add, but which I was too cheap to buy yesterday. Still, the beans make it a complete meal, albeit a nice, light one.
Put bread, tomatoes, basil, beans, and onion into a large bowl. Whisk together remaining ingredients.
Pour enough dressing over the salad to moisten it, tossing it together with your hands, then let it sit for around half an hour to get soggy.
Taste, and add more dressing if it needs it (although the tomatoes will have given off a lot of juice by now, so it may simply need a bit of salt.