In a 4-1/2-quart Dutch oven or casserole, layer the meats, allspice, and salt. Add onions and water; pack down tightly. Press a piece of waxed paper or parchment paper on top of the layers. Place a tight cover on top of the Dutch oven or casserole.
Bake in a 300 degree F oven for 4 to 5 hours or until meat is tender.
To serve, spoon over hot mashed potatoes or cooked wild rice. Makes about 12 servings.