Place clean, chopped, skinless chicken, roast and seasonings in a large pot and simmer for 1 1/2-2 hours or until meat falls away from bones. Debone chicken and cut roast into 1 inch pieces. Return bones to pot and continue cooking until stock is required.

Peel and grate potatoes. Place pulp in cloth bag, and squeeze until all the water and starch is removed, and the potatoes are quite dry. Measure the liquid from the potatoes then discard the liquid.

Loosen squeezed potatoes in a large pan, and gradually add the hot stock in the amount equal to the liquid removed from potatoes. Stir slowly to scald potatoes until they look jelly-like while making sure there are no lumps. Add margarine to potatoes and mix until melted.

Cover the bottom of two 17x12x2 inch pans with half of the potato mixture. Cover layer of potatoes with chicken and pork. Cover with remaining potatoes. Bake in a preheated 400 degree oven for 1 1/2-2 hours, or until crust forms on top. Serve immediately.