In a small bowl, combine 1 teaspoon of the pepper blend, 1/2 teaspoon of the salt, and the garlic. Sprinkle evenly over chicken. In a large skillet, heat oil over medium heat. Add chicken and onions; cook about 15 minutes or until chicken is tender and no longer pink (170 degrees F) and onions are tender, turning chicken once and stirring onions occasionally.
Remove chicken from skillet; slice crosswise into strips. Return chicken to skillet; add tomatoes, tomato paste, ginger, the remaining 1/2 teaspoon pepper blend, and the remaining 1/4 teaspoon salt. Cook and stir just until heated through.
Meanwhile, cook spaghetti according to package directions. Drain. Return spaghetti to the hot pan; stir in pesto.
Serve chicken and tomato mixture on top of pesto-coated spaghetti. If desired, top with shards of Parmesan cheese. Makes 4 servings.