Preheat oven to 350 degrees F.  Grease the bottom of a 9×13” baking pan or dish. Set aside.

In the bowl of a food processor, place 2 cups of flour and the salt and pulse once or twice to combine. Cut 1 cup (2 sticks) of butter into pieces, then add to flour mixture. Pulse again until butter is the size of peas. Add one tablespoon of ice water at a time, pulsing after each addition until moist crumbs form. (Avoid adding too much water – you still want a crumbly texture.)

Pour the crumbs into the prepared baking dish and evenly spread across the bottom, pressing gently down with your fingers.  Bake 20 to 25 minutes or until edges are lightly golden. Remove from oven and allow to cool slightly

While the crust is baking, peel and slice your apples, then place in a large mixing bowl. Add 1 cup sugar and cinnamon, then toss to coat the apples. Pour the apple slices over the baked crust and spread evenly in the pan.

Place the remaining 1 cup flour, ½ cup butter, and 1 cup sugar into the bowl of the same food processor. Pulse to combine until the mixture resembles coarse crumbs. Evenly sprinkle the mixture on top of the apples in the baking pan.

Bake for 60 to 70 minutes or until golden brown and the apples are hot and bubbly. Cool on a wire rack until firm. (You may refrigerate the bars.)  Cut into 12 large squares or 24 smaller squares.