Use this recipe in our Classic Coconut Cake.
Preheat oven to 350 degrees. Brush two half-sheet pans with butter and line with parchment. Brush the parchment with butter. Set aside.
Whisk the flour, baking powder and salt in a medium bowl; set aside. Stir together the milk, cream of coconut, and vanilla; set aside. Beat the butter in a mixer bowl until pale and fluffy, about 3 minutes. Gradually add 2 cups of sugar in a steady stream; mix until pale and fluffy, about 3 minutes.
Reduce speed to low. Add the flour mixture in three additions, beginning and ending with the flour, scraping down the bowl after each addition of liquids; mix until just combined. Raise speed to medium and beat for 30 seconds until smooth. Transfer to a large mixing bowl.
In a clean mixing bowl, whisk the egg whites and remaining 1/2 cup of sugar until soft peaks form. Stir one-third of the egg whites into the batter to lighten, then gently fold remaining egg whites in two additions. Divide batter into prepared pans and smooth the top with an offset spatula. Firmly tap the pans on a work surface to release any air bubbles.
Bake for 15-17 minutes until cake springs back to the touch. Do not over-bake. Cool in pans for 15 minutes, then invert onto a wire rack. Remove the parchment, reinvert, and cool completely.