Moravian sugar cake

1 cup hot mashed potatoes
1 package dry yeast, dissoved in 1 cup lukewarm water
2 eggs, slightly beaten w/1 teaspoon salt
1 cup sugar
1/2 cup margarine melted with 1/2 cup lard or Crisco
4 cups flour -- before sifted

Beat well and let rise 5 hours. Stir down dough and spread thin on pan, with only bottom greased. Let rise 2 hours. Put holes 1/2 inch apart and fill with cold butter. Sprinkle with brown sugar and cinnamon. Bake at 35o degrees for 25 minutes.

Source: Sister Bay (Wisc.) Moravian Church, "The Moravian Women's Fellowship Cook Book" (1970).