Невероятно мягкое и воздушное дрожжевое слоеное тесто,которое просто тает во рту.Слойка Свердловская

The Sverdlovsk puff is tenderness itself: a rather sweet, incredibly soft and airy yeast puff pastry that simply melts in your mouth. On top - crispy streusel and sour cream, which adds a zest to this fragrant and very tasty homemade pastries.
Ingredients
Warm milk 180 ml
Sugar 50 g
Salt 0.5 tsp
Vegetable oil 50 ml
Egg white 1 piece
Yeast fresh 15 g or dry 5 g
Flour 380 gr
Streisel:
Flour 100 gr
Sugar 100 g
Vanilla sugar 1 tsp
Butter 70 gr
Raisins 80 gr
Sour cream filling:
Sour cream 125 gr
Sugar 25 g
Corn starch
For lubrication:
Egg yolk 1 piece
Milk 1 tbsp.l