Make the dough: in a large bowl combine All-Purpose Flour with a pinch of Salt. Mix in warm Water, Neutral Oil and a splash of White Vinegar until a shaggy dough forms. Turn out and knead until smooth and elastic, about 8–10 minutes, then wrap and let rest at room temperature for at least 1 hour (this relaxes the gluten so the dough can be stretched paper-thin).
Soak the raisins: place Raisins in a small bowl and cover with Dark Rum for 10–15 minutes, then drain (reserve any remaining rum for the filling if you like).
Prepare the apple filling: peel, core and thinly slice the Tart Apples. Toss the slices with Granulated Sugar, Ground Cinnamon, Lemon Zest and Lemon Juice until evenly coated; set aside so the flavors meld.
Toast the breadcrumbs: melt about 2–3 tablespoons of Unsalted Butter in a skillet over medium heat, add Fine Dry Breadcrumbs and a tablespoon of sugar, and cook, stirring, until the crumbs are golden and fragrant. Remove from heat and let cool slightly.
Stretch the dough: on a lightly floured surface or clean cloth, roll the rested dough into a large thin rectangle. Then gently stretch it with your hands (or the backs of your knuckles) until nearly translucent with slightly thicker edges — the center should be very thin.
Assemble the strudel: brush the stretched dough lightly with melted butter, sprinkle the toasted breadcrumbs evenly over the dough (this absorbs excess juices), then arrange the apple mixture in a line along one long edge. Scatter the drained rum-soaked raisins over the apples.
Roll and seal: fold the short edges over the filling, then carefully roll the dough into a tight log using the cloth to help lift and roll. Place the seam side down on a parchment-lined baking sheet and brush the top generously with more melted butter.
Bake: preheat the oven to 375°F (190°C) and bake the strudel until deep golden and crisp, about 30–40 minutes. If the top browns too quickly, tent loosely with foil for the last 10–15 minutes.
Finish and serve: let the strudel cool slightly so the juices set, then dust with Powdered Sugar before slicing. Serve warm on its own or with vanilla ice cream or whipped cream.
