
Coat the chicken pieces with melted butter, working in thoroughly. Season with salt, pepper, garlic and onion powders, and other seasonings as desired. Spray roasting pan with non-stick spray and place chicken in pan. Top with sliced onions. Cover pan and roast for 20 minutes.
Remove pan, and spoon out some of the drippings into a sauce pan over medium heat. Whisk in flour to make a roux; then add warm chicken stock whisking continuously.
Pour gravy over the chicken and return to oven, but this time do not cover. Roast another 20 minutes. Remove from oven; spoon thickened gravy over all the pieces. Return to the oven for another 10 minutes.