Ultimate Coconut Cake

Directions

1. Heat the oven to 350°F. Grease two 9-inch cake pans and line the base with parchment paper, then grease the parchment paper.
2. Make the cake: In a medium bowl, whisk the flour, baking powder, salt, and cinnamon to combine. In the bowl of an electric mixer fitted with the paddle attachment, cream the butter and sugar until light and fluffy, 4 to 5 minutes.
3. Add the eggs one at a time, beating on medium speed until each is incorporated and scraping the bowl out well before adding the next addition. Add the vanilla and coconut extract and mix to combine, 30 seconds more.
4. Add half of the flour and mix on low speed to incorporate. With the mixer running, add the buttermilk in a slow, steady stream and mix to fully combine. Scrape the bowl well, then add the coconut and mix to combine.
5. Divide the batter evenly between the two cake pans and spread into an even layer. Transfer to the oven and bake until a toothpick inserted into the center comes out clean, 30 to 35 minutes.
6. Cool in the pans for 10 minutes, then run a spatula around the outside edge and invert onto a cooling rack to cool completely.
7. Make the filling: In a medium pot, bring the coconut milk and cream to a simmer. In a medium bowl, whisk together the sugar, cornstarch, and salt. Whisk in the eggs. When the coconut milk mixture comes to a simmer, add about 1/4 of it to the eggs while whisking constantly to temper the mixture.
8. Add the egg mixture back into the pot while whisking constantly to combine. Continue to cook over medium-low heat, stirring constantly, until the mixture thickens and fat bubbles appear in the center of the pot. Stir in the butter and vanilla.
9. Strain the filling into a medium bowl and stir in the coconut. Cover directly with plastic wrap and refrigerate until well chilled.
10. Make the frosting: In a medium pot, heat the coconut milk until it’s fluid—whisk occasionally until the solids have “melted” and it’s one uniform consistency, 1 to 2 minutes. Add the sugar and stir until fully dissolved. Bring the mixture to a simmer, reduce heat to low, and cook until the mixture is reduced by just over half. I place a spatula into the pot at the beginning of the cooking to sort of visually mark the height of the liquid, then continue to do this to check until it’s reduced properly, 35 to 40 minutes. Cool completely (this can be done up to 1 week ahead and held in the fridge—bring to room temp before using).
11. When the coconut mixture is cool, place the butter in the bowl of an electric mixer fitted with the whip attachment. Whip the butter on medium speed until visibly lightened, 2 to 3 minutes. Add the coconut milk mixture, vanilla extract, and salt and whip for 1 to 2 minutes until well combined, very smooth and fluffy. Transfer about 1/4 of the frosting into a pastry bag and cut 1/2-inch opening from the end.
12. Assemble the cake: Use a serrated knife to remove the domed top of the cakes, if desired, and then cut each cake into 2 layers—you should have 4 layers total.
13. Place one layer on a cake turntable, platter, or cake stand. Pipe a ring of frosting around the outside edge of the cake. Use an ice cream scoop (about 1/4 cup in size) to scoop 4 scoops of filling into the center and spread into an even layer. Place another layer of cake on top, and repeat this process—continue until you’ve used all the filling and layers.
14. Apply a thin all over “crumb coat” of the frosting, and chill the cake for 10 to 15 minutes. Frost the cake with the remaining frosting, and press coconut into the frosting all over the cake.