pie crust

In baking, a crust is the outer, hard skin of bread or the shell of a pie. Generally, it is made up of at least shortening or another fat, water, flour, and salt. It may also include milk, sugar, or other ingredients that contribute to the taste or texture. An egg or milk wash can be used to decorate the outside, as well as coarse sugar. A good crust contributes to a delicious pastry.