– active sourdough starter – potatoes – potato water or milk – all-purpose flour
Roughly mash your cooked potatoes with some milk or the water they were cooked in. Leave some large chunks for texture – no need to mash it all completely.
After transferring your mashed potatoes to a mixing bowl, add salt, sourdough starter, and flour to get a sticky dough. Cover the dough with an airtight material and let the dough rest for 30 minutes.
After 30 minutes, do some stretch and folds or coil folds, whichever you prefer. For best results, do 4 sets of stretch and folds or coil folds, which should take about 1 hour.
After you’ve completed your folding, let the dough rise for about 5 – 7 hours at room temperature. Make sure to cover it to prevent it from drying out.
Shape the dough: Transfer the dough to a lightly floured surface. Pick up one end of the dough, pull it a little, and then fold it over to touch the end on the other side, pressing them together on top of the dough.