Brooklyn blackout cake

Brooklyn blackout cake is an intensely chocolatey layer cake made with plenty of cocoa, generously filled with rich chocolate pudding, coated in a thick layer of chocolate frosting and finished with dark chocolate cake crumbs. It is not overly sweet, while the sour cream in the frosting helps balance the richness perfectly. The cake originated in New York, where it was initially known simply as „chocolate cake”. Its famous name emerged during the Second World War, when blackouts were carried out along the Brooklyn waterfront to allow American ships to leave the harbour unnoticed. This cake is rich, deeply chocolatey, tender in texture and wonderfully decadent. Interestingly, you don’t even need a mixer to make it. While assembling, some of the pudding may spill out around the edges, but it will firm up as it chills, and the thick layer of frosting and cake crumbs will conceal any imperfections. If you’re a fan of chocolate cakes, I highly recommend giving it a try!

Ingredients for the chocolate cake layers:

• 260 g plain flour
• 250 g light brown sugar
• 80 g cocoa powder
• 2 teaspoons bicarbonate of soda
• 1 teaspoon baking powder
• a large pinch of salt
• 250 ml buttermilk or kefir
• 125 ml sunflower or rapeseed oil
• 2 large eggs
• 1 teaspoon vanilla extract
• 1 cup freshly brewed hot coffee or boiling water

All ingredients should be at room temperature.

In a large bowl, combine the buttermilk, oil, eggs, vanilla and sugar. Whisk until well combined. Sift the flour, cocoa powder, bicarbonate of soda and baking powder directly into the mixture. Add the salt and whisk only until combined. Gradually pour in the hot coffee (or boiling water), whisking continuously. Divide the batter evenly between two 20 cm cake tins lined with baking parchment.

Bake at 180°C for approximately 35–40 minutes, or until a skewer inserted into the centre comes out clean. Remove from the oven and leave to cool completely.

Once cooled, slice each cake horizontally into two layers to create four cake layers in total. Crumble one of the least attractive layers into fine crumbs; these will be used for decoration.

Ingredients for the chocolate pudding filling:

• 30 g cocoa powder
• 35 g potato starch
• 310 ml double cream
• 4 egg yolks, from large eggs
• 310 ml milk
• 120 g light brown sugar
• a pinch of salt
• 1 teaspoon vanilla extract
• 130 g milk chocolate, finely chopped

All ingredients should be at room temperature.

Place the cream, sifted cocoa powder and potato starch into a saucepan and whisk until smooth. Add the egg yolks, milk, sugar and salt. Whisk thoroughly and place over medium heat. Cook, whisking frequently, until the pudding thickens and comes to a boil. Once boiling, continue cooking for a further 1–2 minutes, stirring constantly. Remove from the heat and add the vanilla extract and chopped chocolate. Stir until melted and smooth. For an extra-smooth pudding, pass it through a fine sieve. Cover with cling film, ensuring it touches the surface of the pudding, and leave to cool completely, about 2 hours.

Once chilled, stir the pudding and divide it into two portions. Place the first cake layer onto a serving plate and spread with half of the pudding. Top with the second cake layer and spread with the remaining pudding. Finish with the third cake layer. Spread the pudding slightly away from the edges, as it will naturally move towards them under the weight of the cake. Chill for several hours, preferably overnight.

Ingredients for the chocolate frosting:

• 250 ml double cream
• 3 tablespoons golden syrup, runny honey or maple syrup
• a large pinch of salt
• 340 g dark chocolate (around 60% cocoa solids), finely chopped
• 190 g sour cream
• 30 g butter

All ingredients should be at room temperature.

Bring the cream, golden syrup and salt to the boil in a saucepan. Remove from the heat and add the chocolate, sour cream and butter. Stir occasionally until the chocolate has melted and the frosting is smooth. Leave to cool for approximately 1½ hours, stirring every 30 minutes, until the frosting thickens enough to hold its shape and no longer slides off a spoon. At first, the mixture may appear slightly split, but as it cools and thickens it should become smooth and spreadable.

Assembly:

Remove the chilled cake from the refrigerator. Spread the chocolate frosting evenly over the top and sides of the cake using an offset spatula. Press the reserved cake crumbs onto the sides of the cake. Chill for a further 3 hours before serving.

Store the Brooklyn blackout cake in the refrigerator.

Enjoy!

Recipe adapted from a Bon Appétit recipe.