Slow-Cooker Chicken & Orzo with Tomatoes & Olives

Cut each chicken breast half into 4 pieces. Combine the chicken, broth, tomatoes, onion, lemon zest, lemon juice, herbes de Provence, salt and pepper in a 6-quart slow cooker. Cook on High for 1 hour, 30 minutes or on Low for 3 hours, 30 minutes. Stir in orzo and olives; cover and cook until the orzo is tender, about 30 minutes more. Let cool slightly. Sprinkle with parsley before serving.