Cook chicken and then cut into small pieces, set aside.
For a gravy, melt and brown butter.
Add four heaping tablespoons whiteflour. Stir well.
Add 1 quart water, seasoning salt, and salt. Heat until thickened, stirring well.
Add brown gravy. Stir in Velveeta cheese.
Mix liquid with chicken pieces and put into the bottom of a large casserole dish.
Top with 3 quarts prepared mashed potatoes.
Put potatoes on top of gravy and chicken mix.
Drizzle with brown butter.
Bake at 275 1 ½ hours or until heated through.