Preheat oven to 325 degrees F. Grease and flour two six inch round cake pans or spray with flour-added cooking spray and line bottoms with parchment circles.

Measure and assemble all ingredients.

Stir baking soda into buttermilk and set aside.

Beat egg whites using the whisk attachment of the stand mixer. Scrape them into a bowl to wait.

In the same stand mixing bowl, beat butter, shortening, sugar and salt until light and creamy. Add egg yolks one at a time, beating well after each addition and scraping the bowl often. Beat in vanilla.

By hand or using lowest speed of mixer, add flour and buttermilk/soda mixture alternately to creamed mixture, beginning and ending with flour. Fold in the beaten egg whites.

When egg whites are incorporated, fold in the pecans and coconut. Batter should be thick and light. Scrape into prepared pans dividing evenly (about 16 oz per pan)

Bake at 325 degrees for 35-40 minutes or until cakes tests done.

Allow the cakes to cool for about 10 minutes in the pans, then transfer to a wire rack. When cakes are cool, split them horizontally to make four layers.

Frosting: Beat the butter and cream cheese until smooth. Add vanilla. Gradually add powdered sugar. Beat until well blended. Frost the cakes and stack.