Chop rather finely cold roast beef or pieces of beefsteak, also chop twice as much cold boiled potatoes. Put over the fire a stewpan or frying pan, in which put a piece of butter as large as required to season it well, add pepper and salt, moisten with beef gravy if you have it, if not, with hot water; cover and let it steam and heat through thoroughly, stirring occasionally, so that the ingredients be evenly distributed, and to keep the hash from sticking to the bottom of the pan. When done it should not be at all watery, nor yet dry, but have sufficient adhesiveness to stand well on a dish or buttered toast. Many like the flavor of onion; if so, fry two or three slices in the butter before adding the hash. Corned beef makes excellent hash.
Source:
The Whitehouse Cookbook (1887)
