The oven must not be too fierce, and ample time should be allowed.

Baked potatoes require quite two hours.

This only refers to those baked in their jackets.

When potatoes are cut up and baked in a tin they require some kind of fat, which, of course, in vegetarian cookery must be either oil or butter.
POTATOES, MASHED .-- What may be termed high-class mashed potatoes are made by mashing up ordinary boiled potatoes with a little milk _previously boiled_, a little butter, and passing the whole through a wire sieve, when a little cream, butter and salt is added.
In private houses mashed potatoes are generally made from the remains of cold boiled potatoes, or when the cook, in boiling the potatoes, has made a failure.

Still, of course, potatoes are boiled often expressly for the purpose of being mashed.