Melt 2 T butter in Dutch oven over medium-high heat. Add onion; cook and stir 3 to 5 minutes or until softened. Remove from pan; set aside. In same Dutch oven, melt quarter c butter; add chicken and cook 8 to 10 minutes or until golden brown, turning once. Add tomatoes, wine and reserved onion. Bring to a boil. Reduce heat; simmer uncovered 10 to 15 minutes or until chicken is no longer pink. Stir in frozen vegetables and pasta. Bring to a boil. Reduce heat; simmer 3 to 5 minutes or until vegetables are crisp-tender. To serve, place 1 chicken breast half in each of 4 large shallow soup bowls; ladle hot soup over chicken. Garnish with Parmesan and parsley.