Grind your saffron with a little salt in a mortar.
Infuse in a little warm broth and let it rest in the refrigerator covered overnight.
Heat the oven to 200ºC (400ºF)
On a parchment paper-lined baking sheet, place peppers covered with oil, saffron salt and pepper. Place in the oven for 25 minutes.
In a large skillet, add 30 ml of oil, brown the onions with a pinch of saffron salt. Add garlic and thyme, continue cooking for 2 minutes. Add the tomatoes and vinegar and cook until the liquid has almost evaporated. Set aside in a deep ovenproof dish.
In the same pan, add the remaining oil. Brown eggplant and zucchini, a few slices at a time.
Place on top of tomatoes, eggplant, zucchini and peppers together. Add saffron salt and pepper. Put in the oven for 30 minutes.
Add saffron maceration, mix everything together. Cook for 10 minutes.
Let cool a little. Add fresh basil and a drizzle of olive oil.