3 chicken breasts, boiled and shredded* 2 cups chicken stock (reserved from boiling chicken) 1 stick of butter 2 cups Bisquick or self-rising flour 2 cups milk 1 can cream of chicken soup
1 tablespoon chicken bouillon granules or 3 cubes
salt and pepper to taste (careful adding salt; the bouillon and soup are pretty salty)
 (*you can use any chicken you choose)
Place boneless, skinless chicken breasts in sauce pan with enough water to cover the chicken. Cover and bring to a boil, then lower heat to low and cook for 30 minutes or until tender. Remove chicken from stock (reserve the stock) and allow to cool, then shred the chicken.
 Preheat oven to 350*.
When building the layered casserole, do not mix the layers.

Layer 1 - In 9x13 or larger casserole dish, melt 1 stick of butter.  Spread shredded chicken over butter.  Note: If you want to serve this as a pot pie, add a layer of vegetables now. 
Layer 2 - In small bowl, mix milk and Bisquick. Slowly pour over chicken.

Layer 3 - In medium bowl, whisk together 2 cups of the chicken stock, chicken granules and soup. Once blended, slowly pour over the Bisquick layer. (Contents of the pan will be very liquid, don't be alarmed! It will thicken as it bakes and make a delicious, thick sauce.) Bake time varies by oven and pan size used, so bake until the top is golden brown and not gooey, approximately 50-60 minutes.
I've made this with and without adding vegetables and it's great either way. With vegetables it becomes a wonderful, hearty chicken pot pie.