Preheat the oven to 350 degrees. Grease two 8-inch round cake pans and line the bottom with a parchment paper round.
Whisk the flour, cornstarch, baking powder, baking soda, and salt in a medium bowl and set aside.
Combine the butter and half of the sugar in a stand mixer with the paddle attachment. Cream the butter for about a minute or until light and fluffy.
Add the remaining sugar and the oil and mix for another minute until fluffy.
Add the vanilla extract, coconut extract, coconut emulsion, and one egg and mix for 20 seconds. Then, add the other egg, scrape the mixer bowl, and mix for another 20 seconds.
Add half the dry ingredients to the wet ingredients, mixing on low until almost combined. Then, increase the speed to medium and mix until fully combined.
Add the buttermilk and the remaining dry ingredients and mix for 90 seconds until there are no clumps. Then, gently stir in the coconut with a rubber spatula.
Divide the batter evenly between the prepared cake pans and bake for 33 to 38 minutes until a toothpick inserted into the center comes out clean.
Cool the cakes in their pans on a wire cooling rack for 15 minutes. Then, turn the cakes out onto the wire cooling racks and cool completely.
Coconut Buttercream
Whip the butter in a stand mixer for 2 minutes or until light and creamy.
Add the coconut and vanilla extracts and 1 cup of powdered sugar. Mix on medium until blended.
Add the remaining powdered sugar and 3 tablespoon of heavy cream. Mix on low, then increase the speed to medium-high, mixing for 2 to 3 minutes until the frosting is rich, smooth, and creamy.
Construction
Place a cooled cake on a plate or cake stand and frost the top with the buttercream.
Place the second cake on top of the first and frost the top and sides of the cake.
Video
Notes
Store this cake at room temperature for up to 3 days. You can refrigerate the cake for up to 5 days. Refrigeration is also recommended if you live in a warm, humid climate.
For longer storage, chill cake slices and wrap them in plastic wrap. Then, freeze them for up to 2 months in an airtight, freezer-safe container or heavy-duty freezer bags.
To easily turn out your cakes, run a thin knife between them and the edge of the cake pan. Then, place the cooling rack over the pan and invert them. Give the bottom of the pan a gentle tap to help the cake release.
It takes 2 to 3 hours for a cake to fully cool, so give your cakes plenty of time to cool off. Even a slightly warm cake will cause the frosting to thin a bit on contact and slowly slide off of the cake.