Combine water, yeast, and sugar. Stir until dissolved. Set aside. *
Combine milk, potato flakes, salt, and sugar until sugar is dissolved and shortening is melted.
Cool to lukewarm.
Combine with yeast mixture.
Add bread flour and baking soda to yeast mixture.
Stir until smooth.
If necessary, add more bread flour until the dough pulls away from the side of the bowl.
Do not add too much, or the dough will be too stiff for the rolls.
Lightly grease large mixing bowl, place smooth dough ball in pan and lightly grease top.
Cover bowl and let dough rise until double.
When the dough is double, flour surface and roll dough into large rectangle.
Melt 1/4 cup butter and spread over whole surface.
Over half of the surface, lengthwise, sprinkle brown sugar and cinnamon - spread with your fingers if you want to.
Fold the other buttered half over the cinnamon sugar half. Press to remove any bubbles and to adhere both sides of dough to the cinnamon sugar mixture.
From the fold to the long edge, cut into 24 equal strips.
Twist each strip, then tie into a "knot."
Arrange on large baking sheet.
Let rise again.
Preheat oven to 350. Bake for 15-20 minutes.
FROSTING: Melt butter and sugar and boil for 2 minutes. Add milk and heat just until boiling. Remove from heat and cool slightly. Stir in powdered sugar until smooth.