1. Preheat oven to 350 degrees F. Cube butter and line a 9×13 inch pan with parchment paper, spray with cooking spray. Set aside.
2. Add all crust ingredients to stand mixer or food processor, mix until butter is evenly distributed. Mixture will be sandy.
3. Pour ½ crust mixture into baking pan, press down with the flat bottom of a 1 cup measuring cup. Bake for 10-12 minutes, until shortbread crust looks like a cookie, as in it looks like it’s forming a crust. It may not brown, that’s fine.
4. While crust is cooking, add topping ingredients to remaining crust ingredients, mix until it begins to crumble. Refrigerate until use.
5. Next, prepare filling by coring apples and thinly slicing them. Add thinly sliced apples to medium mixing bowl, add remaining filling ingredients (minus caramel sauce) to bowl and mix until all apples are coated. Set aside.
6. Once crust is cooked, spread apple mixture into an even layer on top of crust. Sprinkle topping over apples and bake for 25-30 minutes until topping is golden brown. Let cool at least 10 minutes before you cut and serve them. Drizzle with caramel sauce prior to serving. Refrigerate, covered for up to 4-5 days.