Grease and flour three 8 x 1/2-inch round cake pans.
the King Arthur cake flour, baking powder and baking soda in a medium
sized bowl. Set baking pans and flour mixture aside.
Cream butter until light and fluffy; adding granulated sugar gradually. Beat in the vanilla and almond extract.
Alternately beat in flour mixture and buttermilk on low speed; just until combined.
another bowl, with clean beaters, beat egg whites until stiff peaks
form. Fold the egg white mixture gently into the batter. Next fold in
1-1/2 cups of the chopped pistachios and the orange peel.
into prepared pans and bake in a preheated 350 degree oven for 30 to 35
minutes or until a toothpick inserted into the middle of each cake
layer comes out clean.
Allow cake to cool in pans for 10 minutes and then remove and allow to cool thoroughly on a wire rack. Frost with the white chocolate butter cream frosting and decorate with the remaining 1 cup of chopped pistachios.