Chocolate Cake Recipe

Prepare

Preheat the oven to 350°F (175°C). Grease and line two 8-inch (20 cm) round cake pans with parchment paper and lightly flour the sides.

Mix dry ingredients

In a large bowl, sift (or whisk) together the flour, granulated sugar, cocoa powder, baking powder, baking soda, and salt until uniform.

Combine wet ingredients

In a separate bowl, whisk the eggs, whole milk, oil, sour cream, and vanilla until smooth.

Combine and add coffee

Add the wet ingredients to the dry ingredients and mix until just combined. Slowly pour in the hot brewed coffee and mix on low speed (or stir) until batter is smooth; the batter will be fairly thin—this yields a moist cake.

Bake

Divide the batter evenly between the prepared pans and smooth the tops. Bake for 28–34 minutes, or until a toothpick inserted in the center comes out with a few moist crumbs but not raw batter.

Cool

Let the cakes cool in the pans for 10–15 minutes, then run a knife around the edges, invert onto a wire rack, remove parchment, and cool completely (at least 1 hour) before filling.

Combine sugar and water in a small saucepan and bring to a simmer, stirring until sugar dissolves. Remove from heat, stir in vanilla if using, and cool. Brush a thin layer onto each cake layer before assembling to keep cake moist.

Make chocolate base

Place the chopped semi-sweet chocolate in a heatproof bowl.

Heat cream

Gently heat 1 1/4 cups heavy cream in a small saucepan until it just begins to simmer (do not boil).

Combine and chill

Pour the hot cream over the chopped chocolate and let sit 2 minutes, then whisk until smooth and glossy. Whisk in the butter until melted and combined. Cover and chill in the refrigerator until thickened but still spreadable, about 1–1.5 hours; stir once or twice as it cools to ensure even texture.

Whip (optional)

If you want a lighter filling, when the chocolate mixture is chilled and thick, whip it with the confectioners' sugar and vanilla on medium speed until light and spreadable (about 1–2 minutes). Alternatively, spread as a ganache-like cream if you prefer denser filling.

Heat cream & combine

Place chopped dark chocolate in a medium bowl. Heat 3/4 cup heavy cream until just simmering and pour over the chocolate. Let sit 1–2 minutes, then whisk until smooth. Stir in the tablespoon of butter, if using, for sheen.

Cool to pouring consistency

Let the ganache sit at room temperature until it thickens to a pourable but not too runny consistency (about 20–30 minutes). Stir occasionally. If it becomes too thick, warm gently over a double boiler or microwave in short bursts to loosen.

Level and optionally syrup

If cake tops domed, level each layer with a serrated knife. Place one cake layer on a serving plate or turntable and brush lightly with the simple syrup if using.

Fill

Spread about half of the chilled chocolate cream filling evenly over the first layer (adjust quantity to preference). Top with the second cake layer and press gently to set.

Crumb coat

Apply a thin crumb coat of the remaining chocolate cream (or a thin layer of ganache) around the top and sides to seal in crumbs. Chill the cake 15–20 minutes to set the crumb coat.

Cover with ganache

Place the cake on a wire rack over a tray. Pour the ganache over the center of the cake, allowing it to flow and cover the top and drip slightly down the sides. Use an offset spatula to smooth the top and encourage even drips if desired. Let ganache set for 15–30 minutes at room temperature or refrigerate briefly to speed setting.

Decorate with flakes

Press chocolate flakes or curls around the sides and sprinkle on top as desired. Dust a light sprinkling of unsweetened cocoa powder over the top for a finished look.

Serve

Allow the cake to sit at room temperature 20–30 minutes before slicing for the best texture, then slice with a warm, clean knife. Store leftovers covered in the refrigerator for up to 4 days; bring to room temperature before serving.