Chop cold meat fine, removing the bones, fat and gristle. Put the meat in a pudding dish. To each cup of meat, pour in one-third cup of gravy or one-fourth cup water. Taste, and stir in, if needed, one-fourth teaspoon salt, one speck pepper, and a few drops of onion juice or a little chopped parsley. Spread mashed potatoes as a crust over the meat, bake on the grate of the oven, until golden brown.