Prepare Potato Water: Boil potatoes until soft. Reserve 1 cup of the boiling water. Mash potatoes thoroughly.
Mix Dough Base: In a large bowl, combine mashed potatoes, reserved hot potato water, butter, sugar, salt, and hot water. Stir until butter melts. Let it cool until warm (110°F).
Proof Yeast: In a small bowl, combine yeast, warm water, and a pinch of sugar. Let it rest for 5–10 minutes until foamy.
Combine & Knead: Add eggs and yeast mixture to the potato mixture. Gradually add flour, 1 cup at a time, until a soft dough forms. Knead on a lightly floured surface for 4-6 minutes until smooth.
Rise: Place in a greased bowl, cover, and let rise in a warm, draft-free area for 1 hour, or until doubled in size.
Fill & Bake: Roll out dough, fill with butter, cinnamon, and sugar, and cut into rolls. Let rise for 45 minutes, then bake at 375°F (190°C) for about 20 minutes until lightly browned.
