Combine mashed potatoes, potato water, butter, sugar, salt, and hot water in a large mixer bowl.

Stir until butter melts and let cool.

Combine yeast and warm water in a small bowl.

Add eggs, 2 cups flour, and yeast mixture to the potato mixture.

Continue adding flour, 1 cup at a time, until a soft dough forms.

Knead on a lightly floured surface until smooth and elastic (about 4 to 6 minutes).

Alternatively, knead with an electric mixer using a dough hook.

Place in a greased bowl, turning to coat.

Cover and let rise in a warm, draft-free place for about 1 hour, until doubled.

Punch dough down and divide in half.

Roll one portion of dough on a lightly floured surface to a 12 x 18-inch rectangle.

Spread with half the softened butter.

Combine sugar and cinnamon and sprinkle half of the mixture over the buttered surface.

Roll up tightly, sealing edges.

Cut into 12 slices and place in a greased 13 x 9-inch pan.

Repeat with the remaining dough.

Cover and let rise for 30 to 45 minutes.

Bake in a preheated 350°F oven for 25 to 30 minutes.

Cool for 15 minutes.

Combine icing ingredients and drizzle over the rolls.