25 g fresh yeast
100ml/3½ oz milk
1tbsp vanilla sugar( ½ tsp vanilla extract)
250g/2cups plain flour
2-3 tbsp sour cream
125g(1 stick and 1 tbsp) butter
pinch of salt
3 cups/14oz blueberries
Combine yeast with lukewarm milk and vanilla sugar in a large bowl and mix well. Add the rest of ingredients(except blueberries) and mix it until comes together in a ball. Knead for a few minutes until dough comes cleanly away from your hand. Put aside in a warm place until the dough rises to the top of the bowl.
Preheat the oven to 350 F(180C)
Take the ball of dough out of the bowl and place on the floured work surface. Knead it again,dusting with flour regularly to stop from sticking,then roll the dough out as thin as possible. Use the knife to cut the dough into triangle shapes (3-4inches at their base and 5-5 ½ inches tall).
Place 1tsp of blueberries mixed with ½ tsp of sugar on the shortest side of triangle and roll the edge over the top of the filling. Keep rolling the dough until you get to the end and then bend the ends slightly to create a crescent shape/“rogalik”.
Place the “rogaliki” on the baking tray lined with parchment paper and bake in the oven for 45 minutes.