Name: Brooklyn Blackout Cake Recipe
Prep time: 30 min
Cook time: 45 min
Total time: 4 h 15 min
Cuisine: American
Ingredients: Unsalted butter, room temperature (for pans), ¾ cup (63 g) Dutch-process cocoa powder, plus more for pans; 1½ cups (187 g) all-purpose flour; 1½ tsp. baking soda; ¾ tsp. baking powder; 1 large egg plus 1 large egg yolk, room temperature; 1½ cups (packed; 320 g) dark brown sugar; ¾ cup sour cream, room temperature; 5 Tbsp. vegetable oil; 2 tsp. vanilla extract; ¾ tsp. Diamond Crystal or ¼ tsp. plus ⅛ tsp. Morton kosher salt; ¾ cup hot water; ⅓ cup (28 g) Dutch-process cocoa powder; 5 Tbsp. (35 g) cornstarch; 1¼ cups heavy cream; 4 large egg yolks, beaten to blend; 1¼ cups whole milk; ⅔ cup (packed; 142 g) dark brown sugar; ¼ tsp. kosher salt; 4 oz. milk chocolate, chopped; 1 tsp. vanilla extract; 1 cup heavy cream; 3 Tbsp. golden syrup (such as Lyle’s Golden Syrup); ⅛ tsp. kosher salt; 12 oz. bittersweet chocolate, chopped; ¾ cup sour cream; 2 Tbsp. unsalted butter

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Introduction

Brooklyn Blackout Cake is a rich, decadent chocolate cake layered with smooth chocolate pudding and finished with a luscious bittersweet chocolate frosting. This classic New York dessert is perfect for chocolate lovers craving a moist, intensely chocolatey treat.

A close-up of a three-layer chocolate cake slice on a white plate placed on a white marbled texture. The bottom and top layers are dark, moist chocolate sponge with a soft texture, while the middle layer is a thick, creamy chocolate filling with a rich, smooth look. The outside of the slice is coated with a smooth layer of chocolate frosting with a matte finish. There are some chocolate crumbs scattered on the plate near a metal fork with cake crumbs caught between its prongs. The lighting highlights the glossy parts of the chocolate filling, and the background is clean and white. Photo taken with an iphone --ar 4:5 --v 7

Ingredients

Cake:

Unsalted butter, room temperature (for pans)
¾ cup (63 g) Dutch-process cocoa powder, plus more for pans
1½ cups (187 g) all-purpose flour
1½ tsp. baking soda
¾ tsp. baking powder
1 large egg plus 1 large egg yolk, room temperature
1½ cups (packed; 320 g) dark brown sugar
¾ cup sour cream, room temperature
5 Tbsp. vegetable oil
2 tsp. vanilla extract
¾ tsp. Diamond Crystal or ¼ tsp. plus ⅛ tsp. Morton kosher salt

Pudding:

⅓ cup (28 g) Dutch-process cocoa powder
5 Tbsp. (35 g) cornstarch
1¼ cups heavy cream
4 large egg yolks, beaten to blend
1¼ cups whole milk
⅔ cup (packed; 142 g) dark brown sugar
¼ tsp. kosher salt
4 oz. milk chocolate, chopped
1 tsp. vanilla extract

Frosting:

1 cup heavy cream
3 Tbsp. golden syrup (such as Lyle’s Golden Syrup)
⅛ tsp. kosher salt
12 oz. bittersweet chocolate, chopped
¾ cup sour cream
2 Tbsp. unsalted butter

Instructions

Step 1: Arrange a rack in the center of your oven and preheat to 350°F (175°C). Line two 8×2-inch round cake pans with parchment paper. Grease the pans with unsalted butter, then dust with cocoa powder, tapping out any excess.
Step 2: Sift ¾ cup Dutch-process cocoa powder, all-purpose flour, baking soda, and baking powder into a medium bowl and whisk to combine. In a large bowl, whisk the egg and egg yolk, dark brown sugar, sour cream, vegetable oil, vanilla extract, kosher salt, and hot water until smooth. Gradually whisk in the dry ingredients until just combined.
Step 3: Divide the batter evenly between the prepared pans. Bake for 25 to 35 minutes, or until a toothpick inserted into the center comes out clean. Transfer the pans to a wire rack and let cool completely. Once cooled, invert onto a plate, then invert again. The cake can be baked up to two days ahead and stored tightly wrapped at room temperature.
Step 4: For the pudding, whisk cocoa powder and cornstarch in a large saucepan. Add heavy cream and whisk until smooth with no lumps. Stir in beaten egg yolks, whole milk, dark brown sugar, and kosher salt. Cook over medium-high heat, whisking occasionally until it reaches a boil. Reduce heat and cook for 1 to 2 minutes more until thick and smooth.
Step 5: Remove pudding from heat. Stir in chopped milk chocolate and vanilla extract until the chocolate melts and mixture is smooth. Strain through a fine-mesh sieve into a bowl. Cover with plastic wrap pressed directly onto the surface to prevent a skin, and chill for at least 2 hours.
Step 6: For the frosting, bring heavy cream, golden syrup, and kosher salt to a boil in a saucepan over medium-high heat. Remove from heat and stir in bittersweet chocolate, sour cream, and unsalted butter. Let sit, stirring occasionally, until melted and smooth. Transfer to a bowl and let thicken at room temperature, stirring every 30 minutes, until spreadable, about 1½ hours. If too warm, chill briefly and stir to adjust consistency.
Step 7: Using a serrated knife, carefully slice each cake layer in half horizontally. Set aside the three prettiest layers for assembly. Crumble the remaining layer into fine crumbs to use later.
Step 8: Remove plastic from chilled pudding and whisk vigorously until smooth. Spread half the pudding over the first cake layer on a platter. Top with a second cake layer, cut side down, and spread the remaining pudding. Add the third cake layer cut side down and chill for 1 to 8 hours to firm the pudding.
Step 9: Spread frosting evenly over the top and sides of the chilled cake. Smooth the top as much as possible but don’t worry if the sides look messy; crumbs will help cover imperfections.
Step 10: Press the reserved cake crumbs onto the sides of the cake to completely cover them. Sprinkle crumbs around the edges on top for a finished look.

Tips & Variations

Use Dutch-process cocoa powder for a deep, mellow chocolate flavor.
Room temperature ingredients help create a smooth batter and pudding.
Golden syrup adds a subtle caramel note; substitute light corn syrup if unavailable.
For a nutty twist, add toasted pecans or walnuts to the pudding layer before chilling.

Storage

Store the assembled cake covered in the refrigerator for up to 3 days. To serve, bring cake to room temperature for about 30 minutes for best texture. Leftover cake can be wrapped tightly and frozen for up to 2 weeks; thaw overnight in the refrigerator.

How to Serve

A two-layer chocolate cake with dark, moist cake layers and light brown chocolate frosting between them and on top, the top frosting has a smooth texture with gentle swirls, the side of the cake is coated with coarse chocolate crumbs, it is placed on a clear glass cake stand against a white marbled background with some cake crumbs scattered on the stand. photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I make the cake layers ahead of time?

Yes, the cake layers can be baked up to two days in advance and stored tightly wrapped at room temperature for convenience.

What if I don’t have Dutch-process cocoa powder?

You can use natural cocoa powder, but the flavor will be slightly more acidic and sharp. To mimic Dutch-process, add a small pinch of baking soda to balance the acidity.