1. Prepare the Pans and Oven:

Make the cake: Preheat the oven to 350°F (175°C).

Butter three 8-inch round cake pans.

Line the bottoms of the pans with rounds of parchment paper.

Butter the parchment paper.

Dust the pans with all-purpose flour, tapping out the excess.

2. Combine Dry Ingredients (Cake):

Whisk the all-purpose flour, cake flour, baking powder, and kosher salt together in a medium bowl. Set aside.

3. Cream Butter and Sugar:

Beat the softened butter and granulated sugar in a large bowl with an electric mixer on medium speed until pale and fluffy, 3 to 5 minutes.

4. Add Eggs and Extracts: Add the whole eggs and egg whites one at a time, beating well after each addition and scraping down the bowl as necessary.

Beat in both the coconut extract and the vanilla extract.

5. Alternate Adding Dry and Wet Ingredients: Reduce the mixer speed to low.

Gradually beat in the flour mixture in three batches, alternating with the whole milk, beginning and ending with the flour mixture.

Beat until just incorporated. Be careful not to overmix the batter.

6. Bake the Cake Layers:

Divide the batter evenly among the prepared cake pans.

Bake until the cakes are golden brown around the edges and a toothpick inserted into the centers comes out clean, 40 to 45 minutes.

7. Cool the Cake Layers:

Transfer the cake pans to wire racks.

Let the cakes cool in the pans for 15 minutes.

Then, carefully remove the cakes from the pans, remove the parchment paper. And return the cakes to the wire racks to cool completely.

8. Make the Swiss Meringue Buttercream:

While the cakes are cooling, make the frosting.

Combine the granulated sugar and egg whites in a heatproof bowl (the bowl of your stand mixer is perfect).

Set the bowl over a pan of simmering water (do not let the bowl touch the water). This creates a double boiler.

Whisk constantly until the sugar is completely dissolved and the mixture is warm to the touch, 3 to 4 minutes.

Remove the bowl from the pan.

Beat with a mixer on medium speed until the mixture is thick and glossy, about 5 minutes.

Increase the speed to medium-high and beat until stiff peaks form and the bottom of the bowl is cool to the touch, about 7 minutes more.

Reduce the speed to medium-low. Add the softened butter, a few tablespoons at a time, beating well after each addition. (It’s okay if the frosting looks separated at first – just keep beating on medium-high speed until it comes back together and is smooth again.)

Add both the coconut extract and the vanilla extract, and the pinch of kosher salt.

Continue beating until the frosting is fluffy, 3 to 5 minutes.

9. Assemble the Cake:

Trim the tops of the cooled cake layers with a long serrated knife to make them level, if necessary.

Place one cake layer on a cake stand or platter.

Spread with 1 cup of the frosting.

Place the second cake layer on top. Spread with another 1 cup of frosting.

Place the remaining cake layer on top.

Spread the remaining frosting over the top and sides of the cake, creating a smooth and even finish.

10. Decorate and Serve:

Press the sweetened shredded coconut into the sides of the cake. You can also sprinkle some coconut on top.

Serve and enjoy your beautiful and delicious Coconut Layer Cake!