2Heat oil in a large saucepan over medium heat. Add onion. Cook for 5 minutes or until onion has softened. Add curry paste. Cook for 1 minute or until fragrant. Add chicken. Stir to coat. Add tomato paste, zucchini and carrots. Cook for 1 minute or until all ingredients are coated evenly. Place chicken and vegetables in slow cooker with hot chicken stock. Cook on HIGH for 5hrs. Add rice 30 minutes before serving.