Spread the chopped eggplant, zucchini, red bell pepper, green bell pepper, and tomatoes out onto a baking sheet. Drizzle with olive oil and season with salt and black pepper. Roast for 20 minutes then remove the pan from the oven.
Heat the olive oil in a large saute pan over medium heat. Add the onion and garlic. Stir and cook until lightly caramelized. Add the roasted vegetables to the pan and continue to cook for about 5 minutes.
Add oregano, thyme, and coriander. Adjust the seasoning with extra salt and black pepper if necessary. Stir in the basil and mix well. Serve and enjoy.