1. In a large bowl sprinkle yeast and sugar over warm water (should feel comfortably warm when dropped on wrist) and allow to stand until bubbly, about 10 minutes. 2. Combine butter and milk in top of double boiler over simmering water until butter has melted and milk is warm. Add to yeast mixture and stir until blended. Mix in 2 cups of the flour, 1 cup at a time, and beat well to form a spongy dough. Cover and let rise in a warm place until double in bulk, about 1-1/2 to 2 hours. Stir down with wooden spoon, then add about 3 more cups of flour to form a moist dough that is firm enough to turn out onto a well-floured board. 3. Dip hands in flour and knead dough until smooth and nonsticky, adding additional flour as needed. The dough should be velvety-smooth. 4. Form into a ball and place in a well-buttered, warm mixing bowl. Turn ball of dough so that entire surface of dough is coated with softened butter. Cover and again place in a warm place until double in bulk, about 1 hour. 5. Punch dough down, turn out onto a lightly floured board, and let rest for about 5 minutes. 6. Roll out to a thickness of about 1/2 inch cut with a floured knife first into approximate 2-inch squares, then into triangles. Roll up from wide side to point and place on baking sheet about 1/4 inch apart. When all are prepared, brush with melted butter and again let rise until about double in bulk, about 30 minutes. 7. Bake in a preheated 350'F. oven until lightly browned, 25 to 30 minutes, depending on size. To test for doneness gently tap top of roll for a hollow sound or break open one roll to see if it is sufficiently baked in the center.