Cook chicken in water with salt and pepper. When chicken is done remove chicken from broth and let cool. Once cooled cut into bite size pieces.
Reserve 1 1/2 cups of broth and mix with cream of mushroom soup.
In medium size bowl mix box/bag dressing mix with 1/4 cup of melted margarine
Using an 8x8 casserole dish, layer 1/2 of dressing mix covering the bottom of dish. Sprinkle half the chicken pieces as next layer. Using the rest of the dressing mixture sprinkle on top of chicken layer and then place rest of chicken on this layer. Pour the soup mixture over the entire casserole and bake for 30 minutes at 350.