Slice up three onions and put them in a stewpan with four ounces of butter, and a dozen potatoes; add a quart of water, pepper and salt; put the lid on, and set the whole to stew on a rather brisk fire for about half an hour; by this time the potatoes will be done, and the water sufficiently reduced to furnish only enough for the pie; this stew must be piled up in an earthen pie-dish, covered with a potato crust as directed in No. 502, baked for about half an hour, and served.
Note.—Any kind of fish, or shell-fish, may be added; but when fish is used for a potato pie, it should be freed from bone and skin, and simmered with a little butter, pepper and salt, and when done, placed in neat rows on the top of the potato stew previously to the pie being covered in. In this case the pie will require an extra quarter of an hour's baking.