Peking Duck requires a duck with its head still attached.[citation needed] First, it is inflated with a pump or other object, separating the skin from the body (in ancient times someone with strong lungs would achieve this by blowing through a straw). Then the skin is scalded with boiling water to make it drier and tauter and brushed with molasses so that it acquires a dark, rich color with the slight aroma of caramel during the subsequent cooking process. After drying for half a day, the duck is hung by its neck in a hot oven where it is roasted for an hour or more, during which time the copious fat of the duck melts off and the skin becomes crispy. Because a large oven is required, as well as other complicated preparation techniques, Peking Duck is not usually prepared at home; it is customarily eaten in a restaurant or bought already prepared at shops or restaurants and taken home to eat.

In China, a special breed of duck is reared in the North exclusively for this dish. The ducks are kept in individual cages and force‑fed so that they grow plump and that their muscles would remain tender. Peking duck is thus also called Peking stuffed duck (Simplified Chinese: 北京填鸭; Traditional Chinese: 北京填鴨; Hanyu Pinyin: běijīng tián yā).

The stuffed Peking duck is prized for its layer of fat. However, in the West, non-Chinese customers often find the amount of fat under the duck skin unpalatable. In addition, when regular ducks (as opposed to stuffed ducks) are used, or if the cooking technique is improper, the fat layer can remain congealed after roasting. Due to the unavailability of specially reared ducks outside China, regular ducks are often used. In addition, chefs find creative ways to either remove the fat during the skin separation step or cut strategically placed holes near the bottom of the duck to let the grease drip away during cooking. However, the removal of the fat will affect both the texture and taste of the duck.