Prep the pans and oven: Heat oven to 350°F (175°C). Grease and line two 8-inch round cake pans with parchment. Lightly flour the sides to prevent sticking.

Mix dry ingredients: In a large bowl, whisk 1¾ cups flour, ¾ cup unsweetened cocoa powder, 2 cups sugar, 1½ teaspoons baking powder, 1½ teaspoons baking soda, and 1 teaspoon salt until no streaks remain.

Combine wet ingredients: In a separate bowl, whisk 2 large eggs, 1 cup buttermilk, ½ cup neutral oil, and 2 teaspoons vanilla until smooth.

Bring in the heat: Brew 1 cup hot coffee. You want it hot, not lukewarm. This helps bloom the cocoa for a richer flavor.

Make the batter: Pour the wet mixture into the dry ingredients. Stir until almost combined. Slowly add the hot coffee while whisking. The batter will be thin—that’s correct.

Bake: Divide the batter between the two pans. Bake for 28–34 minutes, or until a toothpick comes out with a few moist crumbs. Avoid overbaking; this cake should be very tender.

Cool: Let cakes cool in the pans for 10 minutes. Turn out onto a rack and peel off the parchment. Cool completely before frosting.

Make the frosting: Melt 6 ounces dark chocolate and let it cool slightly. In a bowl, beat ½ cup softened unsalted butter until creamy. Add 1¾ to 2 cups powdered sugar, a pinch of salt, and 2–4 tablespoons cream, beating until fluffy. Beat in the melted chocolate and 1 teaspoon vanilla. Adjust with more cream or powdered sugar for a spreadable, silky texture.

Assemble: Place one cake layer on a stand. Spread a generous layer of frosting on top. Add the second layer and frost the top and sides. For a simple finish, swoop the frosting with a spatula. Sprinkle with flaky sea salt if you like.

Set and slice: Let the cake sit 20–30 minutes to set the frosting. Slice with a warm knife for clean cuts.