Bring a large pot of salted water to a boil. Add the pasta and cook according to package directions. Drain, then rinse with cold water; transfer to a large bowl.
Meanwhile, in a large nonstick skillet, heat the olive oil over medium-high heat; add the eggplant, season with salt and pepper and cook, stirring, until soft and golden, 7 to 9 minutes. Add to the pasta and toss; let cool to room temperature, about 15 minutes.
Add the mixed greens, bell pepper, mozzarella, onion, parsley and vinegar to the pasta and toss. Season with salt and pepper.