The Ultimate Vegan Brooklyn Blackout Cake has just arrived.
Chocolate Cake. Chocolate Custard. Chocolate Buttercream. Covered in moist cake crumbs.
Covered with a thin veil of chocolate buttercream and loaded up with moist cake crumbs
Before researching the unique nomenclature of the Brooklyn Blackout Cake I decided it simply must be because~
You will literally blackout from ecstasy upon eating it!
However the alleged true account of this cakes origin is that it was invented during World War II by a Brooklyn bakery chain named Ebinger’s.
In recognition of the mandatory blackouts to protect the Brooklyn Navy Yard.
After the war, the name persisted and became a signature offering popular with Brooklyn residents.
While that history is interesting, I think my explanation is more fitting since I repeat:
You may just blackout after eating this cake!
Acetate cake strips are my preference for building a cake like this so I can pour the hot custard into the layers, rather than cooling the custard and spreading it in later.
This method allows the custard to set in the cake for a very smooth clean layer
You will of course need to buy the Acetate Cake strips but this is one of the most valuable “extras” in the bakery kitchen
Used for a multitude of my cold preparation desserts, to me they are invaluable.
Of course you can build the cake traditionally with cold custard and a buttercream dam around the edges.
But either way you cannot ice this cake until it is completely cold and set.
Once it is though, give it a thin crumb coat of that chocolate buttercream and slather on those big fluffy, moist chocolate cake crumbs!
Notes for Success:
Cornstarch is a very difficult ingredient to measure consistently with a volume spoons measure
So while I list both measures below I cannot stress enough how the grams measure with a scale is going to give you the best results.
Many times people have complained that their custard is like rubber and they don’t know why!
This is from a heavy measure of cornstarch when using volume measuring spoon vs the 100% accurate scale measure in grams.
CLICK HERE FOR MORE ABOUT MEASURING WITH A SCALE VS CUPS
Since I only used three layers for the cake the fourth layer was broken up for the cake crumb coating!
If you prefer to bake in 8″ cake pans just divide the batter evenly amongst 3-8″ cakes, for a two layer cake with the third layer being used as the crumble.
CLICK HERE FOR THE FULL YOUTUBE VIDEO TUTORIAL FOR HOW TO MAKE THE BROOKLYN BLACKOUT CAKE
For more of the best chocolate layer cake creations click the links below!
- Fudge 7 Layer Cake
- Andes Mint cake
- Salted Caramel Cake
7 Layer Chocolate Fudge Layer Cake
Brooklyn Blackout Cake

Prepare your cake pans with grease & parchment paper liner and preheat the oven to 350°F The recipe below for chocolate cake will make either 3-8" layers OR 4-7" layers. Which ever size you choose you must use one of the layers for the cake crumb coating
Ingredients
- 1 Recipe Chocolate Cake
- ½ Recipe Buttercream
- Cocoa Powder 4 Tablespoons
- Hot Water 4 Tablespoons
For the Chocolate Custard:
- Plant Milk 2 cup (474ml) * I use soy milk
- Granulated Sugar 1/2 cup (100g)
- Cornstarch 4 Tablespoons (32g) *see notes above
- Cocoa Powder 2 Tablespoons
- Vegan Semi-Sweet Chocolate 2½ ounces (½ cup chopped)
- Vegan Butter 1½ Tablespoons (21g)
- Vanilla Extract 1 teaspoon (5ml)
Instructions
- First prepare the cake recipe as per the instructions on that page.
- For the 7" layers, the oven temperature will stay at 350F but will probably take about 25 minutes to bake, always check at around 18 minutes just to see how it's going
- While the cake is baking prepare the cocoa paste for the chocoalte buttercream by combining the hot water with the cocoa powder, whisk smooth then set aside to cool.
- Prepare the buttercream recipe according to the instructions on that recipe post, and at the last stage of mixing add the cooled cocoa paste. Mix well.
- Once the cakes are baked and cooling, you can then prepare the custard **if you are building the cake as I did with the hot custard, otherwise you can prepare the custard at any time ahead of time and build the cake at a later time
- Prepare the custard by combining plant milk, sugar, cocoa powder & cornstarch in a medium sauce pot over medium to high heat and bring to a boil stirring constantly to avoid scorching the bottom .
- Once it starts to bubble remove from the heat and add the vegan butter & the chocolate, stir to melt evenly throughout.
- Add the vanilla extract stir to mix well.
- Set up your cooled cake layers with the acetate strip and pour the custard into each layer *see video instruction for more clarity.
- Refrigerate the cake until set and then ice with chocolate buttercream
- Use the remaining cake layer to break up into large crumbs to stick onto the buttercream icing.
Notes
Brooklyn Blackout Cake must be kept refrigerated because of the chocolate custard filling.
It will stay fresh, loosely covered for up to 7 days in the refrigerator
Hi Gretchen,
I’m not sure if the cocoa powder for the custard must be natural or Dutch. Which one do you recommend? Thanks.
for custard it doesn’t make a difference
Hi , Can’t thank you enough for this recipe. I tried your recipe – the test was perfect. Just the way I like it. Thanks once again.
YAY! thankyou for the feedback!
Hi….. Cake design are awesome, Your Cake Recipe is really True.
Thanks For Sharing information.!!!…………….
I love this cake! Thank you. I made it for my vegan bakery and it’s a hit! I was wondering if I missed it…do you give a baking time for 3 7″ chocolate cake layers? I only saw it for the sheet cake (40 min). I baked mine in 3 8″ pans in a convection oven for 25 min.
Hey great! Thanks for the comment! I will update the post thanks!
Hi Gretchen: Where doyou purchase the acetate cake strips. Thank you
Hi Paula I link to it in the article but here it is again
CLICK HERE
Did I do something wrong? I made the cakes following the “One Hour ~One Bowl” chocolate cake recipe, but there was only enough batter for two 8″ rounds, not 3. Was I supposed to make the cake layers thinner for this recipe, or should I have 1.5’d it?
Regardless, the cake turned out super delicious, even without the crumb coating!
What height of acetate is the most useful to have on hand?
Thank you for sharing!