Preparation - Grease a 12 cup muffin tin, or line it with paper baking cups. In a large mixing bowl, cream the butter and sugar together, Add the egg yolks and lemon juice and mix well. Separately, combine the flour, baking powder and salt. Add the dry mixture and the grated lemon peel to the creamed mixture and stir just until moistened. In separate mixing bowl, beat the egg whites until stiff peaks form. Fold the beaten egg whites into the batter. Fill the muffin cups two-thirds full. Sprinkle cinnamon-sugar over the batter filled cups. Bake in a preheated oven at 350° for 20 to 25 minutes or until the muffins are light golden brown and a toothpick inserted in the centers comes out clean.
