In stand mixer bowl, add 3 1/2 cups flour, yeast, sugar and salt; mix well. Add warm water and shortening to flour mixture. Using a paddle attachment, blend on low speed until moistened. Beat on medium speed for 3 minutes. Stir in enough remaining flour to make a stiff batter.
Place dough in lightly oiled bowl and turn to grease top. Cover; let rise until indentation remains after poking dough with finger down to second knuckle, about 30 minutes.
Prepare pans: grease two 9x5-inch or 8½x4½-inch bread pans.
Stir down batter. Spread half of batter into each of the prepared pans. Cover; let rise in warm place until batter reaches top of pans, 20 to 30 minutes.
Preheat oven to 375°F.
Bake for 35 to 40 minutes until golden brown. Remove from pans; brush with butter. Cool on wire rack.