Czech Donuts (Větrníky) with Fermented Dough

Method

1. In a small bowl, dissolve yeast in warm water and let sit for 5 minutes until frothy.
2. In a large mixing bowl, combine flour, sugar, and salt.
3. Add softened butter and mix until crumbly.
4. In a separate bowl, mix milk, sour cream, and egg.
5. Gradually add wet ingredients to dry ingredients, mixing until a dough forms.
6. Knead the dough on a floured surface for 8-10 minutes until smooth and elastic.
7. Place dough in a greased bowl, cover with a towel, and let rise in a warm place for 1 hour until doubled in size.
8. Punch down the dough and roll it out into a rectangle.
9. In a separate bowl, mix butter, sugar, and cinnamon for the filling.
10. Spread the filling over the dough, then roll it tightly from one long side.
11. Cut the roll into 12 equal pieces and place them on a baking sheet.
12. Let the pieces rise for 20 minutes, then bake at 375°F (190°C) for 15-20 minutes until golden brown.