Nonstick cooking spray   1 cup finely crushed vanilla wafers (about 30 cookies)   ⅓ cup powdered sugar   3 tablespoon unsweetened cocoa powder   3 tablespoon butter  

*Test Kitchen Tip:

Meringue powder is a mixture of pasteurized dried egg whites, sugar, and edible gums. Look for it in the baking aisle of your supermarket or at a specialty food store.

Make-Ahead Tip:

Bake and cool this pie as directed; place pie in a freezer bag. Freeze for up to 4 months.