What is the importance of adding egg in a pie's crust?

While many bread and pastry products do depend critically on the formation and management of gluten from wheat flours, this is not universally true. read more

Combine flour and salt in processor and blend. Add butter and shortening and process, using on/off turns, until mixture resembles coarse meal. Add 4 tablespoons water; blend in. Add enough additional water by tablespoonsfuls to form moist clumps. Gather dough into ball; flatten into disk. Wrap in wax paper and chill until cold, at least an hour. read more

Flaky pie crust is generally manipulated in a manner which minimizes gluten production: low hydration, resting periods, and minimal mechanical manipulation. The structure and flakiness emerges because the dough is essentially a series of butter flakes or bits, coated in starch. read more