My grandmother did that all the time and I still like it so much.

For a variant, you can add a handful of chopped nuts, such as poops or almonds, to the crumble trim for more crunchy. If you have hard children, try replacing half of the bilberries with strawberries or sliced raspberries for a version with mixed berries. You can also make this gluten-free pie using a gluten-free pie crust and replacing the filling flour with a gluten-free flour mixture.