California Chicken Salad with Creamy Yogurt Dressing

to 8 cups chopped romaine lettuce

- pound grilled chicken breast (, cubed)

seedless red grapes (, halved, cold)

apples (, cored and chopped)

stalks celery (, thinly sliced)

green onions (, thinly sliced, white parts only)

- cup coarsely chopped nuts ((pecans, almonds, walnuts, etc...))

- cup nonfat plain yogurt

- cup nonfat sour cream

dijon mustard

- cup balsamic vinegar

chopped fresh parsley

salt and fresh ground pepper (, to taste)

water