Peel and quarter apples, toss apples until coated with sugar and flour. Fill pie shell with coated apples, piling high in center.

Crumble topping: Mix sugar, flour and butter and crumble over top of apples and place in large paper bag closing bag. Set on bottom shelf of oven rack. Bake at 400 degrees for about 1 hour. This will keep warm in a bag for a couple of hours. NOTE: Bag may smell like it is burning in the oven. Watch!)