Pour flour and salt into a bowl, make a recess in the middle and break an egg into it and pour in water and vegetable oil. With a fork, whisk the liquid with flour, then knead the dough with your hands on a board.
Leave the dough in a warm place for 20 minutes.
Mix cottage cheese and sour cream and, continuing to stir, add vanilla sugar, egg and butter.
Peel the apples, cut into 4 pieces, remove the core, cut into slices.
Roll out the strudel dough on a floured towel and knead it with your hands.
Mix the ground breadcrumbs with cinnamon.
And sprinkle this mixture evenly over the dough layer.
Brush with the curd mass and put it on top of the apples.
Wrap the strudel in a towel.
Grease a baking sheet with butter, lay out the strudel, brush with butter on top. Bake for 30 minutes at a temperature of 220 C.