Brooklyn Blackout Cake

This Brooklyn Blackout Cake has layers of soft chocolate cake, silky chocolate pudding filling, surrounded by chocolate fudge frosting topped with chocolate crumbs. It's decadence on a fork. If that wasn’t enough, it’s gluten free, nut free, eggless and easily vegan! If you're a chocoholic, this is the cake for you!!!

Brooklyn Blackout Cake has always been my favorite cake…FOREVER! It's decadent, moist, rich and this one is allergy friendly! No one would ever believe it! It's always a crowd favorite much like my Chocolate Fudge Cupcakes!

For more chocolate cake recipes, try my Triple Chocolate Cake, Chocolate Blueberry Cake and Chocolate Sprinkle Cake.

Substitutions and Variations

This recipe has not been tested with these substitutions and/or variations due to celiac disease and food allergies. If you change any of the ingredients, please let us know how the recipe turned out in the comments below!

How to Make Brooklyn Blackout Cake

Here are the step by step instructions to make this cake!

Make the Pudding

Step 1: Make the Cornstarch Water

In a small bowl, using a spoon, mix together the cornstarch and water until thin and watery. It will be thick and tacky at first. Set aside.

Step 2: Boil the Water and Mix with Cocoa Powder

In a large heat safe measuring cup, heat the water in the microwave for about 4 minutes until boiling. 

Or you can heat the water on the stove in a pan, until it comes to a rapid boil.

Set a medium saucepan over medium heat on the stove. Add in the boiling water and cocoa powders; whisk to combine.

Step 3: Add in the Sugar and Chocolate Chips

Whisk in the granulated sugar and chocolate chips until they are fully dissolved.

Step 4: Add the Cornstarch Water and Salt and Bring to a Boil

Whisk in the cornstarch water and salt until combined.

Whisking the entire time, bring the pudding to a boil. Once boiling, continue to whisk and boil for one minute. Then immediately remove from the heat.

Step 5: Whisk in the Vanilla and Butter/Vegan Baking Stick

Once off the heat, immediately whisk in the butter or vegan baking stick and vanilla until fully melted and combined.

Leave the pan on a cutting board on the counter, whisking periodically until the pudding has cooled significantly. Then transfer to a heat safe bowl and refrigerate.

You want the pudding thick and cool when you assemble the cake. Make sure the pudding is made ahead of time and is cold from being in the fridge.

Make the Cake

Step 1: Whisk Together all the Dry Ingredients

In a large bowl whisk together the gluten free flour, granulated sugar, cocoa powders, baking powder, baking soda and kosher salt. 

Step 2: Make the Homemade Buttermilk

In a large measuring cup, measure out 1 cup of milk. Add in 1 tablespoon of the white vinegar and stir. Let sit 5-10 minutes and it will appear chunky. That's normal.

Step 3: Make the Cornstarch Water

In a large bowl, using a spoon, mix together the cornstarch and water until thin and watery. It will be thick and tacky at first.

Step 4: Add the Liquid Ingredients

Make a well in the center of the dry ingredients. Add in the cornstarch water mixture, the homemade buttermilk, the warm water, vegetable oil and vanilla. 

Whisk until smooth and combined. If it gets too thick, switch to using a spatula.

Step 5: Scoop the Batter

Using a spatula, divide the batter equally between two greased and parchment lined 8 inch cake pans; smooth the tops with a butter knife. 

Step 6: Bake the Cakes

Bake the cakes in the center rack at 350 degrees Fahrenheit for 47-50 minutes until slightly springy when carefully touched.

Step 7: Cut the Cakes

Remove cakes from the oven and let them cool in the cake pans. 

Once the cakes have cooked completely, take them out of the pan and slice the tops off to create flat surfaces.

Cut or crumble the tops to make tiny crumbs. We will use these later so set them aside.

Make the Chocolate Frosting 

Step 1: Cream the Butter/Vegan Baking Stick

In the large bowl of an electric mixer or using a hand held mixer, beat the butter or vegan baking stick until smooth and creamy. About 2 minutes.

Step 2: Add the Confectioners' Sugar and Cocoa Powders

With the mixer on very low speed, slowly add in the confectioners' sugar and cocoa powders.

Step 3: Add in the Vanilla

Add in the vanilla and beat until combined.

Step 4: Add in the Water 

While the mixer is on, slowly add in the water a little at a time until you get the desired consistency. You may not need to use all the water.

Assembling the Cake

Step 1: Pipe a Ring of Frosting 

Place one layer of cake on the bottom of a cake plate/stand. Place some of the frosting in a pastry bag and pipe a ring around the top edge of the cake.

This is to prevent the pudding from oozing out.

Step 2: Spoon The Pudding

Using a tablespoon, scoop about ¾ of the pudding into the center of the frosting ring.

Step 3: Place the Second Cake on Top

Put the second cake layer on top, bottom side up so the top is nice and flat.

Step 4: Keep the Top and Sides Thin

Use an icing spatula to frost a thin layer of fudge frosting on the top of the cake and a thin layer on the sides.

This will be our crumb layer to just make sure the pudding doesn't ooze out.

Step 5: Chill the Cake

Pop the entire cake in the fridge uncovered for 15-20 minutes. This will make it more stable to work with.

Decorate the Cake

Step 1: Frost The Sides and Push In the Crumbs

Take the cake out of the fridge and continue to frost using an icing spatula.

First frost the sides again and this time immediately press the chocolate cake crumbs into the wet frosting so they stick.

Step 2: Frost the Top

Frost the top of the cake. Press crumbs into the top as well.

If desired, pipe extra frosting swirls around the top of the cake.

Expert Baking Tips

• Use 2 Types of Cocoa Powder- The 2 types of cocoa powders give the cake, frosting and pudding their dark hue. If you only have one type on hand, use natural unsweetened or dutch...just know the color will not be as dark as mine. Do not use dark alone; it will make your cake, frosting and pudding too dry and bitter.
• Make the Homemade Buttermilk- Measure out 1 cup of milk of choice. Add in 1 tablespoon of white vinegar and stir to combine. Let it sit for 5-10 minutes and then stir again. It will appear chunky and that’s normal. 
• Smooth the Batter- Many gluten free batters have a way of staying exactly as they are placed, when baked. When the batter is in the cake pans, gently smooth the tops with a butter knife prior to baking.
• Make the Pudding the Day Before- Although this cake isn’t difficult to make, it is time consuming. The pudding must be thick. The best way for this to be thick enough to spread so it doesn’t ooze out of the cake is to make the pudding the day before the cake. This way when you need to assemble your cake, the pudding is super thick and easy to work with.
• Make the Frosting the Day Before- You don’t have to do this the day before, but it definitely makes assembling the cake a much quicker process. Store the frosting in a bowl covered with plastic wrap in the fridge. When ready to use, let it come to room temperature and rewhip to regain the creamy texture.

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📖 Recipe

Brooklyn Blackout Cake

Author: Lee

This Brooklyn Blackout Cake has layers of soft chocolate cake, silky chocolate pudding filling, surrounded by chocolate fudge frosting topped with chocolate crumbs. It's decadence on a fork. If that wasn’t enough, it’s gluten free, nut free, eggless and easily vegan! If you're a chocoholic, this is the cake for you!!!

5 from 17 votes

Print Recipe Pin Recipe

Prep Time 1 hour hr

Cook Time 47 minutes mins

Chill Time 15 minutes mins

Total Time 2 hours hrs 2 minutes mins

Course Dessert

Cuisine American

Servings 12 Slices

Calories 559 kcal

Ingredients

 

US CustomaryMetric

 

1x2x3x

For the Pudding

• ▢ 2 tablespoons cocoa powder (I use 1 tablespoon Dutch and 1 tablespoon Dark)
• ▢ 2 cups boiling water
• ▢ ¾ cup plus 1 tablespoon granulated sugar
• ▢ 1 ounce chocolate chips
• ▢ 4 level tablespoons cornstarch
• ▢ 3 tablespoons cold water
• ▢ ¼ teaspoon kosher salt
• ▢ 1 teaspoon pure vanilla extract
• ▢ 2 tablespoons unsalted butter or vegan baking stick

For the Cake

• ▢ 1.5 cups gluten free flour (I use a 1:1 gluten free flour with xanthan gum)
• ▢ 1.5 cups granulated sugar
• ▢ ¾ cup cocoa powder (I use ½ cup Dutch cocoa and ¼ cup dark)
• ▢ 1.5 teaspoons baking soda
• ▢ ¾ teaspoon baking powder
• ▢ ¾ teaspoon salt
• ▢ 4 heaping tablespoons of cornstarch mixed with 6 tablespoons of water
• ▢ 1 cup milk
• ▢ 1 tablespoon white vinegar
• ▢ 1 cup of warm water
• ▢ 4 tablespoons of vegetable oil
• ▢ 1 teaspoon of pure vanilla extract

For the Frosting

• ▢ ¾ cup unsalted butter or vegan baking stick
• ▢ 3 ½ cups confectioners' sugar
• ▢ 1 cup cocoa powder (I use ½ cup natural unsweetened or dutch and ½ cup dark)
• ▢ 2 teaspoons pure vanilla extract
• ▢ ½ cup water , room temperature

Instructions

 

Make the Pudding

• In a small bowl, using a spoon, combine the cornstarch and the 3 tablespoons of cold water until smooth. It will be thick and tacky at first. Set aside.
• Boil 2 cups of water (you can do this in a microwave safe bowl or measuring cup as well).
• Over low heat on the stovetop, place the cocoa powder in a pan and pour in the boiling hot water. Whisk to combine. 
• Add the sugar and the chocolate chips, continue whisking to combine. 
• Whisk the cornstarch water mixture into the pan with the chocolate water mixture. Continue whisking. Add the salt and bring to a boil, whisking the entire time. You should see it thickening. If not, increase your heat slightly but be careful not to burn. Let it boil for about a minute, whisking the entire time.
• Remove the pan from the heat and whisk in the vanilla and butter or vegan baking stick. 
• Leave the pan on a cutting board on the counter, whisking periodically until the pudding has cooled significantly. Then transfer to a heat safe bowl and refrigerate. 

  You want the pudding thick and cool when you assemble the cake. Make sure the pudding is made ahead of time and is cold from being in the fridge.

Make the Cake

• Preheat the oven to 350 degrees. Grease two 8 inch round cake pans with vegetable oil, line bottoms with parchment paper and then grease the parchment paper with vegetable oil as well.
• Whisk the gluten free flour, sugar, cocoa powders, baking powder, baking soda and salt in a large bowl until combined and lump free.
• Measure out one cup of milk of choice into a measuring cup. Add one tablespoon of white vinegar into the mix and stir with a spoon. Let it sit for 5-10 min and stir again. It should look slightly chunky. That’s normal.
• In a separate small bowl, combine the cornstarch and 6 tablespoons of water and mix together with a spoon until thin and watery. It will be thick and tacky at first. Set aside.
• Make a well in the center of the dry ingredients. Add the cornstarch water mixture, milk and vinegar mixture, warm water, oil and vanilla. Whisk until smooth. If it starts to get too thick, use a spatula to mix the rest.
• Divide the batter evenly between the two greased cake pans.
• Bake the cakes for about 47-50 min in the center rack of the oven or until the cakes spring back at you when carefully touched.
• Let cool completely in the cake pans. Turn out from pans, and place on cooling racks.
• Once they're cool, use a cake knife cut a thin layer off the tops of each layer to make the cakes level and flat on top.
• Take the extra cake pieces and cut them into tiny crumbs. Set aside.

Make the Chocolate Frosting

• In the large bowl of an electric mixer or using a hand held mixer, beat the butter or vegan baking stick until smooth and creamy. About 2 minutes.
• With the mixer on very low speed, slowly add in the confectioners' sugar.
• With the mixer on low speed still, add in the cocoa powders. 
• Add in the vanilla and beat until combined.
• While the mixer is on, slowly add in the water a little at a time until you get the desired consistency. You may not need to use all the water. 

Assembling the Cake

• Place one layer of cake on the bottom of a cake plate/stand. Place some of the frosting in a pastry bag and pipe a ring around the top edge of the cake. This is to keep the pudding from oozing out.
• Scoop about ¾ of the pudding into the center of the frosting ring.
• Put the second cake layer on top, bottom side up so the top is nice and flat.
• Use an icing spatula to frost a thin layer of the fudge frosting on the top of the cake and a thin layer on the sides. This is our crumb layer so the pudding doesn't ooze out.
• Pop the entire cake in the fridge uncovered for 15-20 minutes. This will make it more stable to work with.
• Take the cake out of the fridge and continue to frost. First frost the sides again and this time immediately press the chocolate cake crumbs into the wet frosting so they stick.
• Frost the top of the cake. Press the crumbs into the top as well.
• If desired, pipe extra frosting swirls around the top of the cake.
• If not serving the cake right away, chill the cake again and take the cake out 15-20 min prior to serving.

Video

Notes

Vegan: Use a dairy free gluten free flour, vegan sugar, vegan baking sticks and non dairy milk and allergy friendly chocolate chips. 

All Purpose Flour: I cannot test this due to celiac disease, but use 1 ½ cups packed AP flour (252 grams) and packed cups of cocoa powder.

Storing: Wrap extra slices in foil and place in a zip top bag in the fridge for up to 2 days. Leave out for an hour on the counter prior to serving. If you want to microwave a slice, do it in 5 second increments and be careful not to burn your mouth on hot pudding.

I don't recommend freezing these slices. The pudding will make the cake layers very wet as it defrosts. 

Nutrition: The info below is a generated estimate and is not guaranteed to be accurate. 

Nutrition

Calories: 559kcalCarbohydrates: 96gProtein: 5gFat: 22gSaturated Fat: 11gPolyunsaturated Fat: 3gMonounsaturated Fat: 5gTrans Fat: 1gCholesterol: 38mgSodium: 375mgPotassium: 248mgFiber: 7gSugar: 75gVitamin A: 446IUCalcium: 76mgIron: 2mg

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