Pick the meat from the back, carcass and neck and mince fine the giblets. Place in a saucepan and add onion, green pepper, and boiling water to the prepared meat. Cook gently for twenty-five minutes, then place shortening and flour in a saucepan. Stir to blend thoroughly and then brown until a rich golden brown. Turn in the prepared emince and stir to mix and season with salt, white pepper, mustard, and poultry seasoning. Make a border of mashed potatoes on a warm platter and fill the emince in the centre of the platter and garnish with finely minced parsley.