Cook potatoes, carrots and celery in chicken broth and water until vegetables are tender. Combine cheese and 1/2 cup of broth from cooked vegetables in microwave-proof bowl. Microwave on High 6 minutes or until cheese melts, stirring every 2 minutes. Add melted cheese to vegetables and broth; stir in parsley. Add more water for thinner chowder. Season to taste with pepper.