In a mixer with a dough hook, blend mashed potatoes and milk. Let cool to a warm but not hot temperature. Add yeast, water and 2 Tablespoons of sugar. Mix well and cover with a dish towel. Let mixture sit for 5 - 10 minutes, allowing yeast to poof and activate. Add eggs, ½ cup sugar, salt, and melted butter. Blend well. Add flour ½ cup at a time until all flour has been mixed in or until dough no longer sticks to the sides of bowl. Coat a large bowl with cooking spray. Add dough and then spray top of dough with cooking spray. Cover with a dish towel and let sit for 1 hour in a draft free spot or until mixture is doubled in size. After mixture has doubled, take all your anger out on it and punch it a few times. Prepare a 9x13 casserole dish and a 9x9 casserole dish for rolls by spraying them generously with cooking spray. Grab approximately 3 Tablespoons of dough and slowly pull ends down and under the dough creating a ball. Place this in the greased casserole dish. You should be able to get 3 across and 4 down, making 12 in the 9x13 pan and 3 across and 3 down in the 9x9 pan, making 9 in the small pan. Cover prepared dough with a dish towel and let rise again for another hour. Preheat oven to 350*F Bake rolls for 25 minutes UNCOVERED or until tops of rolls are golden. Remove from oven and rub butter on top of rolls. Serve immediately.