Prepare Cucumber-Tomato Raita.
. Combine lemon juice and next 8 ingredients in a small bowl, stirring well to form a paste. Cut 3 diagonal 1/4-inch-deep slits across each chicken breast half. Rub spice paste in slits and on all sides of chicken. Cover and let stand 15 minutes.
. Prepare grill.
. Place chicken on grill rack coated with cooking spray; grill 6 minutes on each side or until done. Serve with Cucumber-Tomato Raita.