1.   Preheat oven to 350° and prepare 2 – spring loaded 8 inch round cake pans with butter and parchment paper.
2.  In a bowl, combine 2 cups flour, baking powder, baking soda, and salt, stirring with a whisk.
3.  In mixer bowl, place sugar and 1/2 cup butter, beat at medium speed until well blended, about 5 minutes. Add eggs, one at a time, beating well after each addition. Add flour mixture and nonfat buttermilk alternately to sugar mixture, beginning and ending with the flour mixture. Beat in 2 tablespoons lemon rind and 2 tablespoons lemon juice from two lemons.
4.  Pour batter into prepared pans; sharply tap pans once on counter to remove air bubbles. Bake at 350° for 36 minutes or until a wooden pick inserted in center comes out clean. Cool in pans 10 minutes on a wire rack; remove from pans. Cool completely.

Step 6
Prepare icing, combine powdered sugar and the remaining ingredients (except lemon rind strips) in a mixer bowl; mix until smooth. Spread half of icing on top of a layer. Top with remaining cake layer. Spread remaining half of icing over top of cake. Garnish with lemon rind strips from third lemon. Store cake loosely covered in the refrigerator.