Place all crumble ingredients in a medium-sized bowl and mix together by hand, until you have coarse crumbs. Set aside.

Place peeled and diced apples in another medium-sized bowl and set aside.

Preheat oven to 350 degres Fahrenheit (175 degrees Celsius).

Place all filling ingredients in a small saucepan. Over medium heat, whisk until smooth. Whisk occasionally as mixture slowly reaches a boil and thickens. Remove from heat and allow mixture to cool.

Pour caramel filling over diced apples. Mix well and transfer to a 9×13-inch (23×33-cm) oven-to-tableware. Top with crumble mixture.

Bake for one hour.