Dissolve yeast in warm water. Add shortening, salt, sugar, onion and of the flour. Beat 2 minutes on medium speed, scraping sides. Add the remaing flour and blend with a spoon until smooth. Cover and let rise until double, about 30 minutes. Stir down and spoon evenly into greased muffin tins, full. Let rise until double, about 40 minutes. Bake in a preheated 375F for 20-25 minutes. Brush with butter. Makes 9-12 rolls