I like this dough so much because it can be rolled and re-rolled without toughening up or shrinking once baked.
ingredients
Dough
Filling
directions
Preheat oven to 350 F.
Combine flour, oats, baking powder and salt in a bowl. Cut in butter the texture of coarse meal. Stir sour cream and maple syrup and add to dough, mixing until it just comes together. Chill dough for 15 minutes.
Peel and slice apples. Toss with maple syrup and cinnamon.
On a lightly floured surface, roll out dough to 1/4-inch thick. Slide dough onto a parchment-lined baking sheet. Place apples and all the syrup into the center of the pastry. Dot with butter.
Fold crust over apples in 5 folds, leaving some of the filling visible. Brush with egg wash and bake for 30-40 minutes, until crust is brown and filling is bubbling.