Scrub clean, enough medium-size potatoes (you will be eating the skins) to fill a covered 9×13-inch pan or covered roaster. Slice potatoes into 1/4-or 1/3-inch slices, place in a large bowl or pan. Melt 1 to 2 tablespoons of butter or margarine, add another tablespoon, or more, of cooking oil. Pour over potato slices and stir until are all coated with the shortening. Then mix in a package of dry onion soup and a small amount of salt. Mix until all slices are well coated. Place slices in either covered cake pan
or roaster, bake in hot oven, 400° to 500°, for 30 to 45 minutes, until done.
After you have prepared them once or so, you can use your own judgment as to how much shortening to use. (I like to try to get by on the least amount of shortening as possible, for calorie sake.)