Cook pasta according to package directions; drain.
Meanwhile, heat oil in large saucepan over medium heat. Add onion and cook 3 minutes, stirring occasionally. Add garlic and cook about 1 minute, stirring occasionally. Add chicken and cook about 6 to 7 minutes or until chicken is cooked through, stirring
Stir in tomatoes and bell pepper, and let simmer, stirring occasionally, 4 minutes. Stir in parsley, basil, crushed red pepper, vinegar, salt and pepper. Additional crushed red pepper may be added, if desired.
Add pasta and toss to coat. Serve immediately topped with cheese, if desired.