In a small mixing bowl, combine water, bouillon, onion powder and salt; mix well. Microwave on high for 3-6 minutes, or until water boils. Stir in bulgur. Cover with plastic wrap. Let stand about 30 minutes or until bulgur softens. Drain and press to remove excess moisture. Spread bulgur on large serving platter. Meanwhile, in a 2-quart casserole, combine chicken, tomato, mushrooms and green pepper; cover. Microwave on high for 7-10 minutes or until chicken is no longer pink, stirring twice. Remove the chicken and vegetables with a slotted spoon. Place over bulgur. In a 1-cup measurer, combine dressing and pepper. Pour evenly over chicken and vegetables. Serve warm.