Sweet, flaky apftelstrudel with thinly sliced apples, rum-soaked raisins, & sugary toasted breadcrumbs is the very best way to celebrate Oktoberfest!
Mix water, oil, lemon juice, and salt in a large mixing bowl. Slowly stir in the flour.
Knead the dough in the bowl for about 10 minutes, until smooth and not sticky. Pick up the dough and slam it into the bowl a few times to help the gluten develop.
Brush a clean bowl with oil and transfer the ball of dough to the clean bowl. Brush the surface of the dough with oil and cover with plastic. Let dough rest at room temp for an hour.
Soak the raisins in rum in a small bowl for at least 10 minutes.
Melt butter in a large skillet over medium heat. Add breadcrumbs and toast, stirring constantly, until golden brown.
Remove skillet from heat and whisk in brown sugar, cinnamon, and vanilla. Set aside.
Thinly slice the apples and toss with lemon juice, raisins, and remaining rum in a large bowl. Set aside.
Preheat oven to 375°.
Pick up the dough and begin stretching it with your hands, like it's a pizza crust. Stretch it over your knuckles as paper-thin as you can without tearing, creating a large rectangle.
When the dough is too thin to handle, lay it down on a large, clean towel and stretch out any thick edges.
Facing the dough in landscape orientation, so the long edge is toward you and the short edges are on your left & right, brush the left half of the dough with 1 T. melted butter.
Sprinkle the right side with the breadcrumb mixture and gently press into the dough. Top with apple mixture, leaving about an inch of space from the edges.
Fold the long edges of the dough, top and bottom, over the apple filling & melted butter. Starting from the right edge, begin rolling the strudel up tightly, using the towel to lift.
Set the strudel seam-down on a parchment-lined baking sheet.
Bake at 375° for 35-40 minutes, until pastry is golden brown. Remove from the oven and let cool for at least 10 minutes. Dust with powdered sugar and serve with whipped cream.