Preheat the oven to 375 degrees Fahrenheit. Spray a 15x10x1-inch pan with nonstick cooking spray and set aside.

To make the dough, combine 3 1/3 cups of flour and salt in a large bowl. Using a pastry blender, cut in the shortening until it looks like coarse crumbs.

Add four tablespoons of cold water to the mixture and stir with a fork. Repeat with the remaining water one tablespoon at a time until the dough is moistened. Use your hands to form it into a ball.

On a lightly floured surface, roll the dough into a 19x13-inch rectangle. Wrap it around the rolling pin and roll it into the prepared baking pan. Gently press the dough up the sides of the pan, trimming it to 1/2 inch beyond the edge. Fold the edge over and flute as desired. Chill the pan in the fridge.

In an extra-large bowl, mix the sugar, 1/3 cup flour, cinnamon, and apples until the apples are evenly coated. Carefully spread the apple mixture over the chilled crust.

For the crumb topping, combine the oats, brown sugar, and 1/2 cup flour in a bowl. Cut in 1/2 cup of butter until crumbly and sprinkle it over the apples.

To make homemade caramel, melt 1 cup of brown sugar, 4 tablespoons of butter, half-and-half, vanilla, and a pinch of salt in a saucepan over low heat until smooth. Drizzle the caramel over the crumb topping.

Bake for 35-40 minutes or until the apples are tender and the topping is golden brown. Let it cool before slicing.