Donuts

3 packages yeast Table spoons 1/2 cup warm water 2 1/4 cups milk, scalded, 3/4 cup sugar 1 1/2 teaspoons salt 3 eggs 1/2 cup shortening 7 1/2 cups flour Oil for frying Glaze 1/2 cup butter 3 cups powdered sugar 2 1/4 teaspoons vanilla 4-6 tablespoons evaporated milk (can substitute regular milk or water for milder flavor) If desired separate and add chocolate powder or maple flavoring or other flavor to glaze