Smith Island Cake

Instructions

• Prepare icing: Combine cream and corn syrup in a medium saucepan over medium heat; bring mixture just to a simmer, stirring often. Remove from the heat.
• Place chocolate in a large microwave-safe bowl and pour hot cream mixture over top. Sprinkle with salt and let stand 2 minutes. Whisk until completely smooth and let cool to room temperature, about 1 hour. Chill icing in the refrigerator until thickened and spreadable, about 45 minutes, stirring halfway through.
• Meanwhile prepare cake layers: Preheat the oven to 350 degrees F (175 degrees C). Spray nine 8 1/2-inch round disposable cake pans with cooking spray. Line the bottoms with parchment paper and spray that gently with more cooking spray.
• Beat butter in a stand mixer fitted with the paddle attachment at medium speed until smooth and creamy, about 1 minute. Gradually add sugar and beat until light and fluffy, about 3 minutes. Add eggs, 1 at a time, and beat just until incorporated after each addition. Beat in vanilla.
• Whisk together flour, baking powder, baking soda, and salt in a medium bowl. Add flour mixture to butter mixture alternately with buttermilk in 3 batches, beginning and ending with flour mixture and beating on medium speed.
• Divide batter evenly (about 1 cup each) among prepared pans and smooth with an offset spatula. Bake, in batches, until a wooden pick inserted in center comes out clean, 12 to 14 minutes. Let cool in pans on wire rack 10 minutes. Turn cakes out onto wire racks to cool completely, about 20 minutes.
• Place 1 cake layer on an 8-inch round cake board and spread with 1/3 cup icing using a small offset spatula. Top with another cake layer and spread with 1/3 cup icing. Repeat the process with remaining layers and icing. Coat the top and sides of the cake with a thin layer of icing. Chill cake for 1 hour and reserve remaining icing.
• Place chilled cake on a wire rack over a rimmed baking pan. Microwave reserved icing at medium (50%) power in 30-second intervals, stirring after each one, until smooth and pourable, 1 to 1 1/2 minutes. Pour icing in a slow, steady stream over the top of the cake, starting at the center and moving to the outer edges so it flows down the sides. Smooth out the sides and fill any gaps with a small offset spatula.
• Chill cake until set, about 1 hour. Carefully transfer cake to a serving plate. Serve at room temperature.