The most nutritious way to cook potatoes is in their skins, since most of the vitamins and minerals lie in or just beneath the skin. Baking potatoes in their jackets, therefore, is an ideal way of preserving all the nutrients. Boiling potatoes in their skins has a dual advantage: not only does it prevent the vitamins leaching out into the cooking water but it also ensures that the potatoes hold their shape better.
Throughout this book you will notice that some recipes call for the potatoes to be peeled while in others they are left unpeeled; it is really a matter of personal taste. If you do peel potatoes, peel them as thinly as possible just before cooking. Always boil them in the smallest amount of water and never leave them in hot water after cooking.