Preheat oven to 400 degrees.
Start by coring the apples from the top with a small knife but add a small amount of core to the bottom of the apples.
Evenly divide and fill each apple with butter and brown sugar halfway then completely fill with crumble and pat on the top.
Wrap apples in foil and bake for 25-30 minutes then watch carefully for another 5 minutes to make sure apples are still stable and intact. Remove from oven and allow to cool for 5-10 minutes then serve.