Preheat the oven to 350°F (175°C). Grease and flour three 8x2-inch pans (or 9-inch pans if preferred).

In a mixing bowl, beat the butter at medium speed until softened and smooth. Gradually add the sugar, mixing on medium speed for 4 to 5 minutes.

Add the egg yolks, one at a time, beating after each addition until fully incorporated. Stir in the vanilla extract.

In a separate bowl, whisk together the flour, baking soda, and salt for at least 30 seconds to blend.

With the mixer on low speed, alternate adding the dry ingredients and the buttermilk to the butter mixture, beginning and ending with the dry ingredients. (This means three additions of the dry mixture and two additions of buttermilk.) Mix just until blended after the final addition.

Gently fold in the pecans and coconut using a spoon or spatula until evenly distributed.

In a clean bowl, beat the egg whites on high speed until stiff peaks form. Carefully fold the beaten egg whites into the batter using a spatula or spoon.

Divide the batter evenly among the prepared pans. Bake at 350°F (175°C) for 20 to 25 minutes, or until a toothpick inserted in the center comes out clean.

Let the cakes cool in the pans for 10 minutes, then transfer them to wire racks to cool completely.

Slice the butter and place it in the bowl of your mixer. Beat on low to medium speed until softened and smooth.

Cut the cream cheese into pieces and add it to the butter. Continue beating on low to medium speed until well combined.

Add the vanilla extract and mix until incorporated.

Gradually add the powdered sugar, beating on low speed until fully blended. Increase the speed to medium and beat for about 1 minute, until the frosting is fluffy. Avoid overmixing, as it can make the frosting too soft. If this happens, refrigerate the frosting for 10 to 15 minutes to firm it up.

For best results, use the frosting while it is still cool. If making ahead, refrigerate it and allow it to soften slightly before use (do not microwave). Remix before frosting.

This frosting recipe is sufficient to frost a three-layer 8-inch or 9-inch cake. Ensure the cake layers are completely cool before frosting.

Frost the cake completely with the cream cheese frosting. For added stability, chill the cake during the decorating process as needed (15 minutes in the freezer or longer in the refrigerator).

Once frosted, press the remaining chopped pecans around the bottom half of the cake for decoration.

Alternatively, for a more traditional approach, stir all the pecans into the cream cheese frosting before spreading it over the cake.