Cream butter, then add sugar and continue creaming. Add eggs and mix at medium speed. Mix baking soda with sour cream and add to cookie batter. Mix in juice and rind of orange. At low speed, mix in 3/12 cups flour and baking powder
Drop by teaspoon onto ungreased cookie sheet. Bake at 375 degrees until very lightly browned on bottom and top springs back (about 8 minutes). Cookies shoud be puffy and cakelike. It is best to just 2-3 at first to test. If too flat, add 1/4 to 1/2 more flour (Amount of flour depends on size of orange.) Bake remaining cookies and cool before icing.
For icing, Mix juice and rind of one lemon with sugar gradually, until spreading consistency. Spread on top of each cookie.