Mix the starter, flour, butter, sour cream/yogurt, eggs, salt and vanilla together in your mixer until smooth.
Cover with a damp towel and let sit 6-24 hours on the counter.
The dough will look basically unchanged at this point.
Preheat oven to 375F.
Combine sugar and cinnamon.
Roll dough into a 15×18 inch rectangle and then spread the cinnamon sugar mixture on top of it.
Fold like a letter towards the middle into thirds,
Then turn the dough horizontally and roll into a 1/4 inch rectangle.
Then slice into 1 inch strips.
Grease or cover two baking sheets with parchment paper.
Twist the strips by picking up each end of the strip and twisting them in opposite directions.
Place the twists on the tray next to each other.
Bake for 15 minutes, let cool a bit, then devour!