What is the primary cooking technique used for making Quiche Lorraine?

The primary cooking technique used for making Quiche Lorraine is baking. This classic French dish consists of a savory custard filling, typically made with eggs and cream, poured into a pastry crust that is baked in an oven. The baking process allows the crust to become golden and crisp while cooking the filling evenly, resulting in a rich and flavorful quiche.

Baking is essential in this method because it creates the desirable texture and flavor profile that defines Quiche Lorraine. Other cooking techniques like frying, boiling, or steaming do not achieve the same results that baking does for this specific dish, as they involve different processes and cooking environments that aren't suitable for a custard-based pie.