Set aside one cup of flour. In large bowl mix 5 1/2 to 6 cups flour, 2 tsp. salt, 1/2 cup sugar and 2 pkg. rapid rise yeast. Heat 2 cups water and 1/4 cup shortening to 125 to 130 degrees F. Stir hot liquids into dry mixture. Add one egg. Mix in enough reserved flour for desired consistency. Let rest 10 minutes and knead. Place in greased bowl and cover. Refrigerate at least 2 hours. Use as needed. Bake 12 to 15 minutes at 375 degrees.
For one dozen cinnamon rolls, roll out 1/2 of dough, cover with melted butter and brown sugar, and sprinkle with cinnamon. Roll dough up and cut into 12 pieces. Place in greased 9 x 13 pan and let rise until double, about one hour. When rolls are done prepare powdered sugar glaze and pour over top.