Bring large pot of lightly salted water to a boil. Add pasta, stirring to prevent sticking. Cook until just tender. Drain, reserving ½ cup pastawater; rinse under cold running water and drain well. Transfer pasta to serving bowl.
In large skillet, heat oil over medium heat. Add onion, bell pepper and garlic and cook, stirring often, until soft, about 5 minutes. Add eggplant and tomatoes and cook, stirring often, until the vegetables are tender and tomatoes release their juices, about 20 minutes. Season with salt and pepper. Add vegetables to pasta in bowl.
Add reserved pastawater to skillet and cook over high heat, stirring, until reduced slightly. Add it to pasta and vegetables and toss to combine. Serve pasta topped with basil, croutons sautéed in garlic and grated Parmesan or soy cheese if desired.