Preheat the oven to 190 degrees.
Place the dough on a lightly floured cloth of about 70 by 70 cm. Roll out the dough with a rolling pin to about 30 by 30 cm. Use enough flour to prevent sticking. Then stretch the dough sheet very thinly to a size of about 65 by 65 cm. Use the backs of your hands to prevent your fingers from tearing the dough.
Brush the dough sheet with half of the melted butter. Sprinkle the edge, about 20 cm, that is closest to you with the sprinkles. Place the apple filling on top of this. Roll the dough upwards with the help of the cloth. Place the dough on a baking sheet and brush with melted butter. Bake the strudel for 45 to 60 minutes. Brush the dough with melted butter every 15 minutes.
Allow to cool briefly, sprinkle with icing sugar and serve warm, possibly with whipped cream or crème anglaise.