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.