Preheat oven to 375°.

Peel, core apples and slice into 1/4-inch slices. I use a mandoline to make uniform slices.

Place sliced apples in a large bowl and mix with brown sugar, corn starch and cinnamon. Set aside.

Lightly flour a clean surface. Roll the crust out to about 14 x 20 inches. Press the pie crust into a rimmed sheet pan, I used a 13 x 18 x 1 inch pan. Place the pie crust into the refrigerator while you make the crumb topping.

 Add flour, brown sugar, oats and cinnamon to a large bowl. Slice cold butter into the flour mixture. Mix with a fork, pastry cutter or use your hands to create a crumbly mixture.

Remove pie crust from the refrigerator. Stir the apples. Spoon apples over the pie crust, leaving excess juice in the bowl. Sprinkle crumble mixture over the top in an even layer.

Bake for 40- 45 minutes or until crust and crumble are golden brown.

 Remove from oven to a wire rack. Cool 15 minutes.

Drizzle with caramel sauce.

Slice and serve with a scoop of vanilla ice cream and additional caramel sauce.