Monica, "Crust" refers to a hard, crunchy outer part of some food items such as bread, pizzas and pies. They are found along the perimeter of bread and pies, and the circumference of pizzas. For example, when we order a pizza, we may request for a "thin crust". Hope this helps.

Es la masa con la que se forra el molde del pie :)

Hola, Mónica. Es "la corteza del pay". Saludos.

(Oops, sorry. You are learning Spanish. I don't know the answer).

the hard edge of the pie