Amish Cinnamon Rolls with Caramel Frosting

Rolls:
2/3 cup sugar + 2 tsp sugar, divided
1 cup warm water
2 pkgs yeast (0.25oz) pkts
4 beaten eggs
2/3 cup melted butter
1 tsp salt
1 cup homemade mashed potatoes
6 cups bread flour
Filling:
1 cup brown sugar
2 Tbsp cinnamon
6 Tbsp melted butter
Frosting:
1 stick butter
1 cup brown sugar
1/4 tsp salt
1/4 cup milk
1 tsp vanilla
2 1/2 cup powdered sugar
Notes/Story: 1) Mix 2 tsp sugar, warm water, and yeast. Lets stand 5 min.
2) Mix together the rest of the roll ingredients in a large bowl and add the yeast mixture gently. Cover dough and let rise 2 hrs.
3) While dough is rising, mix together brown sugar and cinnamon. Once the dough has risen, roll out dough in a rectangular shape to about 1/4 inch thickness. Spread with the melted butter and brown sugar and cinnamon mixture. Roll up and cut into 1" slices. Place slices 1" apart on a baking sheet greased with melted butter. Let rise for 1 hr and 15 min. Bake at 350 for 20-25 min.
4) For frosting, melt the butter in a saucepan over low heat. Blend in the brown sugar and salt. Cook on low for 2 min. Stir constantly. Add milk. Remove from heat and add vanilla. Let cool and add powdered sugar. Spread over rolls when rolls cool.
I made this after Thanksgiving 2010 since there was leftover mashed potatoes. These were delicious and couldn't even tell there were mashed potatoes in the rolls.