1. Prepare outdoor grill with medium-hot coals or heat broiler. Oil grill rack. Mix 1/4 cup garlic-flavored oil, oregano, pepper and garlic powder in bowl.
2. Lightly flatten chicken breast halves. Brush both sides of chicken with oil mixture; sprinkle with salt. Grill 3 minutes per side to cook through. Mix pimientos, vinegar and 1 teaspoon garlic-flavored oil in another small bowl. Spoon over chicken.