1 pkg. dry yeast
1/2 tsp. sugar
1/4 c. warm water (105~ to 115~)
1 c. unsalted hot mashed potatoes
1 c. sugar
1/2 c. shortening
1/4 c. butter
1 tsp. salt
2 eggs, beaten
5 to 6 c. all purpose flour
1 c. cold butter, cut into 1/8 inch pieces
1 1/2 c. firmly packed brown sugar
Ground cinnamon

Dissolve yeast and 1/2 tsp. sugar in warm water; let stand 5 minutes. Combine potatoes, 1 c. sugar, shortening, 1/4 c. butter and salt in a large mixing bowl; mix until shortening and butter melt. Stir in yeast mixture. Cover and let rise in a warm place (85°F), free from drafts, about 1 1/2 hours or until spongy. Stir in eggs and enough flour to make a soft dough that leaves sides of bowl. Shape dough into a ball; place in a well greased bowl, turning to grease top. Cover and let rise in a warm place (85°F), free from drafts, about 2 hours or until doubled in bulk. Turn dough out onto a lightly floured surface, and knead 5 minutes or until smooth and elastic. Divide dough in half; pat evenly into two greased 13 x 9 x 2 inch baking pans. Cover and let rise in a warm place (85°F) free from drafts, about 1 1/2 hours or until doubled in bulk. Press slices of butter into dough at about 1/2 inch intervals in rows. Top each slice of butter with about 1 tsp. brown sugar. Sprinkle cinnamon over entire surface.

Bake at 375°F for 20 minutes or until golden brown. Cut into 2-inch squares and serve warm.