

Boil the potatoes in a saucepan until soft.
Drain, then add the sour cream, milk and butter and mash until smooth.In a mixing bowl, stir the flours,yeast, sugar and salt together.
Add half of the eggwash, potatoes mixture then, using a dough hook, mix everything to form a dough.
Add the scallion and continue to knead for about 15 minutes until the dough is smooth and elastic.
Add a little oil to another bowl and add in the dough. Turn over a few times to very lightly coat all sides of the dough.Cover the dough with plastic wrap and allow to rest till double in bulk, about 1 hour. After the dough has risen, pour out onto a clean flat surface. Punch down the dough to release some of the air. Devide the dough into 8 pieces and shape each into a round form.
Place the rounds onto a parchment lined cookie sheet. Cover with plastic warp and allow to rise for another 40-50 minutes.
Brush the rolls with the remaining eggwash and bake into a preheated 350F oven for 22-25 minutes.
Remove and cool on a wire rack before served.