This was my nana’s all-time favorite cake! Now I know why

Combine 1/2 cup of butter and shortening in a large bowl and beat until frothy. While beating, add 2 cups of granulated sugar and mix thoroughly.
Step 3: Dividing the eggs. Gradually beat in the egg yolks to the creamed mixture, followed by 1 tablespoon of vanilla essence. After creaming the mixture, sift the all-purpose flour and baking soda in a separate dish. Alternately add the buttermilk and sifted flour combination to the creamed mixture. Toss in the roasted chopped pecans and flaked coconut.
4. Whip the egg whites into stiff peaks in a separate, clean basin. Lightly combine the cake batter with the egg whites by gently folding them in.
5. Evenly distribute the cake batter into the pans that have been prepared. To make sure each cake layer is cooked through, stick a toothpick into the middle and bake for 25 to 30 minutes.
Sixth, after 10 minutes of cooling in the pans, transfer the cakes to wire racks to finish cooling.