Pie Crust

1. In a large bowl, combine flour and salt.  Mix together.  Using a pastry cutter, cut in butter and shortening until the largest flour coated shortening and butter crumbs are the size of peas.  Add the very cold water a few tablespoons at a time and mix until a dough forms.  Clean hands may be the best tool for this job.  The dough will be slightly crumbly.  Knead together a few times to form a disk and wrap in plastic wrap. Chill for at least 3 hours.  This step can be done in advance, and the dough may be frozen and then thawed before assembling the pie.

Filling

1. In a large bowl, mix apples, brown sugar, granulated sugar, flour and apple pie spice.  Mix until evenly coated.

Topping

1. In a medium bowl, mix oats, brown sugar, flour, and cinnamon.  Add melted butter and stir until small clumps form.

To Assemble

1. Preheat oven to 375 degrees. Remove the dough from the refrigerator and place it between two large pieces of plastic wrap.  Roll from the center, turning the dough as you go, until you have a 13 by 18 inch rectangle.  The dough will be thin.  Remove the top piece of plastic wrap and flip the dough over onto a 10 by 15 inch jelly roll pan.  Remove the second sheet of plastic wrap, and gently press the dough (without stretching it) into the pan.   Roll the overhanging edges of the dough under and press them to the side of the pan.
2. Pour the apple filling into the prepared unbaked crust and spread evenly to the edges of the crust.  It will be full, but the apples will reduce in the oven.
3. Spoon the crumb topping over the apples and spread to the edges.
4. Bake for 40-44 minutes.  The top will be golden brown.  Allow to cool (or not!), then cut into squares and serve with vanilla ice cream.  A caramel drizzle would be a lovely addition.