Ingredients:
150 g of warm milk
60 g of sugar (or to taste)
20 g of fresh yeast (or 6-7 g of dry)
2 eggs (1,5 for the dough, 0,5 for the glaze)
80 g melted butter (not hot)
500 g flour (approximately)
A pinch of salt
For the filling:
40 g butter
30 g of sugar
2 teaspoons of vanilla sugar
To fill:
200 g sour cream (20-25%)
2 tablespoons sugar (or condensed milk)
Vanilla (optional)
Method of cooking:
Heat the milk until lukewarm. In a bowl, mix the warm milk, sugar and fresh yeast. If using dry yeast, use three times less. Stir to dissolve the yeast. Add two eggs, reserving half of one for brushing the buns. Then pour in the melted, but not hot, butter and mix lightly.
Gradually add flour, starting to knead the dough. It should be soft, elastic, not sticky to your hands. You can knead by hand or with a mixer. If you use a mixer, gradually increase the speed. On average, you need about 500 g of flour, but determine the exact amount by the consistency of the dough.

Shape the finished dough into a ball, grease a bowl with oil, transfer the dough to it, cover with a towel and leave to rise in a warm place for an hour and a half. The dough should increase in volume by about half.
When the dough has risen, shape it into a ball, cover and let it rest for another 10-15 minutes. Then roll out the dough into a rectangular sheet measuring approximately 50×40 cm.
For the filling, melt the butter and spread it over the surface of the dough. Mix the sugar with vanilla sugar and sprinkle evenly over the butter. If desired, you can add cinnamon, poppy seeds or raisins.
Roll the dough into a roll, pinch the edges. Divide the roll into 12 equal parts using a string or a sharp knife. Flatten each roll slightly and place on a baking sheet lined with parchment paper. Cover with a towel and leave to rise for another 30 minutes.
Preheat the oven to 180°C. Brush the buns with the remaining egg to give them a golden crust, or leave them ungreased if you plan to use sour cream filling. Bake for about 20 minutes until cooked through.
Meanwhile, prepare the filling. Add sugar or condensed milk to the sour cream, stir until the sugar is completely dissolved. Add vanilla if desired.
Spread the sour cream filling on the finished hot buns. First, spread a teaspoon of the filling on each bun, and then distribute the rest evenly. If desired, you can return the buns to the turned off but warm oven for a few minutes so that the filling soaks in better.