Alright, who else’s jaw is unhinged at the sight of this stunner?
Happy Sundae Thursday, kids! Wow, that’s mighty confusing. What’s even more befuddling is that National Hot Fudge Sundae Day is on Saturday. Why isn’t it on Sunday? Who created this goddamn food calendar?
At any rate, today I’m sharing this absolutely flabbergasting dessert that combines the concept of the layered fudgy sundae with an indulgent dual-layer cake situation with a brownie slab and a dark chocolate cake slab My Hot Fudge Brownie Sundae Layer Cake looks complex and yes, does take some time (and a lot of dish-washing) but overall is pretty uncomplicated to create.
Plus, no extensive decorating prowess required, just some strategic drizzling and a pop of bright red cherries atop.
This would serve as an eye-popping birthday cake for a kid’s or adult’s party, a showstopper for a parent night doodad once school starts or just to celebrate Saturday’s misplaced but very valid food holiday.
If you’re REALLY feeling sassy, scoop some vanilla ice cream on your slice. Now you’ve got a real crazy Sundae on your plate.
Double Trouble
This cake features two distinct layers: a brownie layer and a chocolate cake layer.
The brownie layer contains my standard recipe for fudge brownies, one which you saw if you peeped my Old School Frosted Fudge Brownies last week, for instance. Same recipe, same goodness.
Microwave butter with chocolate chips until fully melted, then whisk in sugar and brown sugar until fully incorporated.
In your stand mixer, beat three eggs until very whippy and frothy. Pour in the butter-chocolate mixture along with some instant coffee or espresso (optional, but fabulous for emphasizing the chocolate flavor) and vanilla extract. You’ll get a nice smooth chocolate base from all this.
Add in flour, cocoa powder, and baking powder. The batter will be super thick and you might want to stick your whole hand in it. Don’t do that.
Grab your two 9-inch cake pans and grease lightly with oil or butter. Cut out two circles of parchment to fit in the bottom of each pan. This step majorly helps prevent stickage. Dump your brownie batter into one of the lined cake pans.
Tip: To easily match the size of the bottom of your pan, fit your sheet of parchment into the pan and remove to see where the indents are created in the paper, and cut around said indents.
Next, the cake layer. I use my classic dark chocolate cake recipe, which very easily halves and results in a perfect slab every time. This recipe appears in all of my chocolate cakes and cupcakes.
Beat vegetable oil, brown sugar, and sugar until incorporate, then whip in your eggs, one at a time; vanilla extract and plain Greek yogurt follow. Then, flour, cocoa powder, black cocoa powder (if you don’t have this, more regular cocoa is fine), baking powder, baking soda, and salt. With the mixer running on low, stream in your buttermilk.
Pour the cake batter into your second cake pan. Pop both in a 350 degree oven for 30-40 minutes. I found that my cake layer is finished by 35 minutes, and the brownie layer needs an extra 5 minutes or so since it is much fudgier and thicker.
Let the cake layer cool for 10 minutes in the pan, then loosen the edges with a knife and flip onto a wire rack. The brownie layer is a bit trickier and needs much more time to cool before attempting to remove it. My best practice? Cool on the counter 20 minutes, in the pan, then set the pan in the fridge for at least 25 minutes. I kept mine chillin’ for 30 or so while I popped out to the pool for a swim. The brownie will remove much more easily when it is more solidified.
Big Fudge
Next up: the sawce. Very easy to make. Melt some dark or semi-sweet chocolate chips in a small saucepan with heavy cream and cocoa powder. Whisk until thickened and the cocoa is dissolved, about 4-5 minutes. Move the pan off the burner and stir in some vanilla. You will use the whole amount called for in the recipe card.
Once the layers are fully cooled, prepare your cake batter frosting. This is amazing and the closest thing to the essence of ice cream without the ice cream itself.
Tip: I like to chill the layers overnight to ensure they are properly set up and ready to receive frosting. Also helps with time management and ensure I don’t get overwhelmed by how much time this whole process takes.
For the buttercream, beat butter with vanilla and cake batter extracts. In 1/2 cup increments, with the mixer running on medium low, add your powdered sugar. Stop the mixer and use a spatula as needed to scrape down the bowl and ensure everything is melding nicely. As the frosting thickens, pour in a tablespoon of heavy cream at a time to soften the texture.
Once you’ve added 6 cups of powdered sugar, crank the mixer up and whip until very fluffy and light. You may need an additional spoonful or two of heavy cream to create the finishing silky texture.
Pop the brownie layer onto a cake stand or flat plate. The brownie should go on the bottom since it’s heavier. Frost the top with a generous amount of buttercream, about 1/2 inch or so thick. Place the chocolate cake layer on top and frost all around. Use a bench scraper to smooth out the frosting.
Tip: If needed, level the top of the your chocolate cake layer with a serrated knife to prevent any weird leaning or unevenness. I find that I rarely need to do this with my chocolate cake recipe, but it’s a useful thing to know how to do.
Use a spoon or offset spatula to spread the hot fudge sauce on top. You may need to gently microwave the sauce first for 15-20 seconds to soften if it’s been sitting on the counter for a bit. Push the sauce down the sides to create the pretty dribbling effect you see in the photos.
Let the sauce set for 15 minutes. Use any remaining buttercream and a 1M tip to pipe swirls on top of the cake. Place a maraschino cherry on each swirl.
Phew! You did it! Now cut out a big hunk and enjoy the fruits of your tireless labor.
Leftovers? Cake will last on the counter, covered, for up to 3 days, after which I’d move it to the fridge for up to a week. Slices will freeze well for up to 3 months.
Black cocoa powder? King Arthur makes a good bag, otherwise you can find various brands on Amazon.
Cake batter extract? Mccormick is the most accessible brand and the one I use!
Cheers, friends!
Tried this recipe out? Leave a rating and comment below with your thoughts, and don’t forget to come say hi on Instagram and show me what you made!
Cake it till you make it:
Salted Caramel Chocolate Cupcakes
hot fudge brownie sundae layer cake
Ingredients
brownie layer
- 10 tbsp butter
- 1 cup dark chocolate chips
- 1 cup sugar
- 1/4 cup dark brown sugar
- 3 large eggs, at room temperature
- 1/2 tsp instant coffee/espresso (optional)
- 1 tsp vanilla extract
- 3/4 cup all purpose flour
- 1/3 cup unsweetened cocoa powder
- 1/2 tsp baking powder
chocolate cake layer
- 1/2 cup vegetable oil
- 1/2 cup dark brown sugar
- 1/4 cup sugar
- 2 large eggs, at room temperature
- 1 tsp vanilla extract
- 1/4 cup plain whole milk Greek yogurt, at room temperature
- 1 cup all purpose flour
- 1/4 cup unsweetened cocoa powder
- 1 tbsp black cocoa powder (or more regular cocoa)
- 3/4 tsp baking powder
- 1/4 tsp baking soda
- 1/2 tsp kosher salt
- 2/3 cup buttermilk, at room temperature
hot fudge sauce
- 1/2 cup dark chocolate chips
- 1/4 cup heavy whipping cream
- 1 tbsp cocoa powder
- 1/2 tsp vanilla extract
cake batter buttercream
- 2 sticks butter, softened
- 2 tsp vanilla extract
- 1 tsp cake batter extract
- 6-7 cups powdered sugar
- 1/4 cup heavy whipping cream
- maraschino cherries, for garnish
Instructions
- Preheat oven to 350 degrees. Lightly grease two 9-inch cake pans. Cut out two circles of parchment and fit one to the bottom of each cake pan.
Brownie layer:
- In a microwave-safe bowl, melt the butter and chocolate chips for 1 minute. Stir until the bowl is no longer warm. If needed, heat an additional 20-30 seconds until totally smooth. Whisk in the sugars.
- In a large bowl, beat the eggs on medium-high speed until very frothy and bubbly, about 3-4 minutes. Lower the speed and mix in the butter and sugar mixture, then the vanilla and instant coffee (if using).
- Add the flour, cocoa powder, and baking powder. Mix until just combined. Pour the batter into one of the prepared cake pans.
Chocolate cake layer:
- In a large bowl, beat the oil, brown sugar, and sugar for 2-3 minutes until combined. Whip in the eggs, one at a time, then the vanilla and yogurt. Add the flour, cocoa powder, black cocoa powder, baking powder, baking soda, and salt. With the mixer running, stream in the buttermilk until the batter is just combined. Do not overmix. Pour into the second cake pan.
- Bake the layers for 30-40 minutes. Start checking the cake at 30 minutes, as it may bake faster than the brownie layer.
- Cool the cake layer in the pan for 10 minutes, then run a knife around the edges to loosen and invert onto a wire rack. Peel off the parchment from the bottom.
- The brownie layer will take longer to cool sufficiently. Cool on the counter for 20 minutes, then refrigerate at least another 25 minutes before attempting to remove. To do this, run a knife around the edges to loosen, then carefully invert onto a plate, then flip upright onto the wire rack.
hot fudge sauce:
- In a small saucepan, whisk the chocolate chips, heavy cream, and cocoa powder until the granules dissolve and the sauce thickens and becomes super smooth, about 4-5 minutes. Remove the pan from the heat and stir in the vanilla. Let cool.
Cake batter buttercream:
- Whip the butter, vanilla, and cake batter extracts until combined, then add 6 cups of the powdered sugar, in 1/2 cup increments as the mixer is running on medium low speed. Add heavy cream 1 tablespoon at a time to smooth out the texture. Crank the mixer to high, and beat until very light and fluffy, about 2-3 minutes. You may need an extra tablespoon of two of cream to achieve the desired texture. Scrape down the sides of the bowl with a spatula, as needed, to properly incorporate all the ingredients.
- Place the brownie layer on a cake stand or flat plate. Frost the top generously, about 1/2 inch thick, then set the chocolate cake layer atop and frost thoroughly. Smooth the frosting out as best you can with a bench scraper.
- Spread the hot fudge sauce across the top of the cake with an offset spatula or spoon, letting some dribble down the sides. Let set for 15 minutes. Use any remaining buttercream to pipe swirls on top of the cake. Garnish with maraschino cherries!
