Bring water, 1 tablespoon basil and 1 teaspoon bouillon to a boil. Add pasta; cook to desired doneness as directed on package. Drain; cover to keep warm.
Meanwhile, heat oil in large skillet over medium-high heat. Add chicken and garlic; cook and stir 6 to 9 minutes, or until chicken is no longer pink. In small bowl, combine 1/2 cup water and cornstarch; blend well. Stir into chicken.
Add onions, olives, 1/4 cup basil and 1/2 teaspoon bouillon; cook and stir 2 to 3 minutes or until mixture is slightly thickened and glazed. Pour over pasta; add tomatoes and toss to coat. Garnish with fresh basil, if desired.