Prepare the dough. Sift the flour into a deep bowl. Make a small depression in the middle. Break an egg into this depression, add water and salt. Mix all the ingredients with a spoon. The dough will be thick and stick to your hands. Sprinkle some flour on the table and lay out the resulting dough. Pour vegetable oil over it and knead the dough until it stops sticking to your hands. Wrap the dough in cling film and put it in the refrigerator for 30 minutes.
Prepare the filling. Finely chop the apples. Mix the apples, sugar, cinnamon, breadcrumbs, pine nuts and lemon zest. Leave the filling for 15 minutes.
Stretch the dough. Take the dough out of the refrigerator. Roll it out to a thickness of 5 mm using a rolling pin. Then take the edges with both hands and slowly pull the dough. Turn it around its axis a little and pull it again. Be careful and do not rush. Continue stretching the dough until its thickness becomes 1-2 mm.
Prepare the strudel. Melt the butter and grease the resulting layer of dough with it. Spread the filling over the dough. Roll it into a roll. Pinch the edges of the roll. Carefully transfer the strudel to a baking sheet. Grease with egg yolk. Bake in the oven at 180 degrees for 50 minutes.