Dissolve yeast in milk; add 2 cups flour and mix well; let stand in a warm place for 1/2 hour. Beat egg yolks and egg together and add sugar, shortening, vanilla (or nutmeg), salt, 4 1/2 or 5 cups flour and orange rind (or lemon). Add this to yeast mixture. Let rise to double bulk (about 1 hour). When light turn out on floured board. Roll to 1/2 inch thickness. Cut with donut cutter and lay on waxed paper until very light. Fry in deep fat until lightly brown.