Preheat the oven to 350 F
Combine the cake flour, salt, and baking powder. Mix or sift together until well combined.
3 cups cake flour, 1 tsp salt, 4 1/2 tsp baking powder
Add the egg whites, 1 1/2 cup butter, and granulated sugar into a large mixing bowl.
6 large egg whites, 1 1/2 cup butter, 2 3/4 cup granulated sugar
Mix until well combined, then add in the vanilla and coconut extract.
1 tbsp coconut extract, 2 tsp vanilla extract
Add in 1/4 cup coconut flakes
1/4 cup sweetened coconut flakes
Gradually start adding in the dry ingredients (flour, salt, baking powder), alternating with the buttermilk.
1 1/4 cup buttermilk
Mix the batter until everything is well incorporated, then divide and pour into two prepared 9-inch pans.
Bake for 25-30 minutes.
Remove the cakes from the oven, remove from the pan, and cool on a cooling rack.