Wash and scrub the baked potato(es) and bake it in the oven on the middle rack at 400°F for about 1 hour or until soft when pierced with a fork.
When the potatoes have cooled, peel them and cut them in small pieces then mash them with the 1 stick of butter. Add in the 3 eggs and 1 cup of the flour and continue mashing until smooth.
In the bowl of your mixer add the water, yeast and sugar, stir and let it sit for about 10 minutes until yeast has dissolved and it becomes foamy.
Add potato mixture to the yeast mixture and using the paddle attachment mix for a couple minutes. Add 3 more cups of flour, one cup at a time and mix well. If the dough is too dry add a bit more water, but I didn't need too, there was enough moisture from the sweet potatoes. After the 3 cups of flour have been added in the dough should still be sticky.
Sprinkle about half a cup of flour over your work surface and scrape the dough onto the floured surface. Knead the dough until it's smooth and elastic, I only kneaded for about a minute, but it depends how sticky your dough is. Butter or oil a large bowl and place the dough in there, cover it with foil and let sit in a warm place until it doubles in size, about an hour.
In the meantime, make the filling by mixing all the ingredients in a bowl using a fork.
After the dough has doubled in size, preheat the oven to 425°F. You will need a large baking sheet for this.
Turn the dough onto your floured surface and roll it out so that it's about 24 inches by 16 inches and about ½ inch in thickness. Sprinkle or spread the filling evenly over the dough. Working carefully, from the long edge, roll the dough down to the bottom edge.
Carefully cut the roll into 12 equal size rolls, so the easiest is to cut the roll in half then cut each half in half and then each quarter in 3 so you end up with 12 equal size rolls. Transfer the rolls onto the baking sheet, wrap with plastic wrap and let rise for another 20 minutes.
Bake the rolls for about 15 to 20 minutes until they are golden brown.
In the meantime make the icing by whisking all the icing ingredients together. Spread the icing over the warm rolls and enjoy!