Southern Chocolate Buttermilk Church Cake

Preheat the oven to 175°C (350°F) with the baking rack positioned in the center.

Coat the bottom and interior sides of two 23 cm round cake pans with a thin layer of vegetable oil using a pastry brush, then line the bottom of each pan with a circle of parchment paper.

Sift the all-purpose flour, granulated sugar, 75 g unsweetened cocoa powder, baking soda, baking powder, and 5 g fine sea salt through a fine-mesh sieve into a large mixing bowl.

Whisk the sifted dry ingredients together for 30 seconds until uniformly dispersed and aerated.

In a medium mixing bowl, whisk together the buttermilk, vegetable oil, eggs, and 10 ml vanilla extract until emulsified and smooth.

Pour the liquid buttermilk mixture into the dry ingredients and mix with a silicone spatula just until dry streaks disappear.

Pour the hot brewed coffee slowly into the batter in three additions, stirring gently with a silicone spatula after each addition until the batter is smooth, thin, and lump-free.

Divide the batter equally between the two prepared 23 cm round cake pans, weighing each pan on a measuring scale to ensure equal distribution.

Place both cake pans side by side on the center rack of the oven at 175°C (350°F) and bake for 30 to 35 minutes until the center reaches at least 98°C (208°F) and a toothpick inserted into the middle emerges clean or with only a few dry crumbs.

Transfer the cake pans to a wire cooling rack and allow them to rest in their pans undisturbed for 15 minutes.

Invert the cake pans onto the wire cooling rack, peel away the parchment paper circles, and allow the cakes to cool completely to room temperature for 1 hour.

Place the chopped unsweetened chocolate into a heatproof bowl set over a small saucepan of gently simmering water, stirring constantly with a silicone spatula until melted and smooth, then set aside to cool until lukewarm to the touch.

In the bowl of a stand mixer fitted with the paddle attachment, beat the softened unsalted butter on medium speed for 3 minutes until smooth, aerated, and pale ivory in color.

Pour the lukewarm melted chocolate into the creamed butter and beat on medium-low speed for 1 minute until completely homogeneous.

Add the sifted powdered sugar, 30 g sifted unsweetened cocoa powder, heavy cream, 5 ml vanilla extract, and 2 g fine sea salt to the mixer bowl, then mix on low speed for 30 seconds to incorporate the powders before increasing to medium-high speed and beating for 2 minutes until glossy, light, and spreadable.

Place one cooled cake layer flat-side down on a cake stand or serving plate, and spread 180 g of chocolate frosting evenly across the top surface using an offset spatula.

Set the second cake layer upside down on top of the frosted layer so the completely flat baked bottom serves as the level top of the cake.

Spread the remaining chocolate frosting over the top and around the sides of the cake using the offset spatula, sculpting soft swoops and swirls across the surface before slicing.