For crust, mix cornmeal, flour, baking powder, sugar, salt, baking soda, oil, buttermilk, and egg in mixing bowl until smooth. Pour into greased 8-inch x 8-inch baking pan and bake at 375 degrees F for 20 to 25 minutes until done.
Remove from oven and let cool completely. When cool crumble corn bread and place 3 cups of cornbread crumbs in mixing bowl.
Add 1/2 cup melted butter to crumbs and mix well, set aside.
In a saucepan on medium low heat, melt butter and saute onions and celery until transparent, stirring occasionally. Add chicken broth, cream of chicken soup, salt, and pepper. Stir until well blended and soup is incorporated. Add chicken, stir and blend until mixture reaches a low simmer. Cook for 5 minutes, remove from heat.
Place chicken mixture in buttered casserole dish 2 1/2 quart, or individual casserole dishes (about four). Spoon cornbread crumb topping on top of chicken mixture, do not stir in chicken filling. Place baking dish in preheated oven at 350 degrees F for 35 to 40 minutes. The crumbs will turn a golden yellow.
A viewer, who may not be a professional cook, provided this recipe. The FN chefs have not tested this recipe and therefore, we cannot make representation as to the results.