This Brownie Birthday Cake is the perfect way to celebrate- decadent layers of brownie (instead of cake) with chocolate fudge frosting and sprinkles! It's perfect for any brownie lover!
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This brownie birthday cake is a fun twist for all your celebrations! This birthday cake is made from two layers of delicious, rich, and fudgy brownies and topped with fudge chocolate frosting! Plus lots of sprinkles, because duh!
This recipe is perfect if you want to bake a birthday cake, but really don't love cake. If brownies are more your love language, this is the cake for you! Plus it doesn't take long to make and you only need a few staple ingredients.
I’ve already got a few birthday desserts here, like my Funfetti Cookie Cake, but I wanted to have a brownie version! If you're looking for another fun way to make brownies, try my Brownie Crinkle Cookies!
Why You Need This Brownie Birthday Cake
- These are cakey brownies so they’re stable enough to stack! Even though the brownies are dense, they are still super flavorful and have the perfect texture for a cake.
- This fudge frosting is super decadent, but you could use a vanilla buttercream or cream cheese frosting instead.
- Rainbow sprinkles are a must for birthday cake brownies, but you can leave those out if you prefer! Or add other fun toppings like m&ms, Reese's cups, crushed peppermint, etc.
- This is the perfect birthday cake for someone who loves brownies! (I am a brownie lover and this is the ultimate cake, trust me)!
Recipe Ingredients
Here are some notes on a few ingredients- please see the full ingredient list in the recipe card below!
- Cocoa Powder: make sure you’re using high-quality cocoa powder as it will make all the difference here!
- Flour: this recipe has only been tested with all-purpose flour.
- Unsalted Butter: I always use unsalted butter in my recipes, this is important so you can control the amount of salt!
- Rainbow Sprinkles: totally optional but they’re so fun!
Step-by-Step Instructions
Step 1: Preheat your oven to 350°Fahrenheit. Spray two 8-inch round cake pans with non-stick spray and line the bottom of each pan with parchment paper.
Step 2: In a large microwave-safe bowl, melt the butter. Add the light brown sugar and whisk until combined. Add the eggs one at a time, whisking after each addition. Finally, add the vanilla extract.
Step 3: Mix in the cocoa powder, flour, and salt. Mix until there are no more streaks of flour.
Step 4: Pour the batter into the two pans and bake for 30-35 minutes. A toothpick inserted into the center should come out clean. Allow the brownies to cool in the pan for 10 minutes, then flip them onto a wire cooling rack to cool completely.
Step 5: Use an electric mixer to beat the butter until smooth. Add the cocoa powder, powdered sugar, milk, and vanilla extract. Mix on low until combined, then increase the speed to medium and beat for 1 minute until smooth.
Step 6: Once the brownie layers have completely cooled, place one layer onto a plate and top it with half of the frosting and sprinkles (if using)! Add the second brownie layer on top and cover with the rest of the frosting and sprinkles. Enjoy your birthday cake brownies!
Frequently Asked Questions
This brownie cake is much cakier/denser than regular brownies, which are typically fudgy and can be soft. Instead of single brownie bars, this birthday brownie is layered like a cake!
If you aren’t a fan of fudge frosting, use my cream cheese frosting instead! Vanilla buttercream would also be great on these. If you're short on time, canned frosting from the grocery store would be a perfect substitution.
You can make the brownie layers ahead of time! Bake the brownie layers as directed, then once they’re completely cool wrap them tightly in plastic wrap. You can also make the frosting the day before, storing it in an airtight container in the fridge overnight. When ready to assemble, remove the brownies from the plastic wrap and add the frosting.
Tips and Tricks
- Let the brownie layers cool completely before assembling, otherwise, the fudge frosting might melt right off!
- I recommend ensuring your ingredients are at room temperature before starting, especially your eggs.
- Make sure to measure your flour correctly! While we want the brownie layers to be cakey, we don’t want them to be dry and make your brownies crumbly.
- These brownies are RICH, so I suggest slicing them into small slices. You won't need a huge slice to feel satisfied.
- These are my favorite sprinkles to use!
Storing & Freezing
You can keep slices of this brownie birthday cake in an airtight container for up to 2-3 days, or up to a week in the fridge.
You can also freeze slices for up to 2 months, either wrapped in saranwrap/tinfoil or stored in an airtight container. To thaw, defrost in the fridge overnight before enjoying.
Want to try more brownie recipes?
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📖 Recipe
Brownie Birthday Cake
Ingredients
- 1¼ cup unsalted butter melted
- 2½ cup light brown sugar packed
- 4 large eggs at room temperature
- 2 teaspoon vanilla extract
- 1½ cups cocoa powder
- ¾ cup all-purpose flour spooned and leveled
- ¾ teaspoon salt
Icing
- 5 tablespoon unsalted butter at room temperature
- ½ cup cocoa powder + 2 tbsp
- 2½ cups powdered sugar
- ⅓ cup milk
- 1 teaspoon vanilla extract
- rainbow sprinkles optional
Instructions
- Preheat the oven to 350° F. Spray two 8-inch round cake pans with non-stick spray and line the bottom with parchment paper. Set aside.
- In a large microwave-safe bowl, melt the butter. Add in the brown sugar and whisk until fully combined. Add in the eggs, one at a time, whisking in between. Then add the vanilla extract.
- Mix in the cocoa powder, flour, and salt until just combined and no streaks remain. The batter will be thick.
- Pour the batter equally into the two prepared pans. Bake in the oven for 30-35 minutes, or until a toothpick inserted into the center comes out clean. Allow the brownies to cool in the pan for about 10 minutes, run a sharp knife around the edges to release the brownies, and then flip them onto a wire cooling rack to cool completely.
- To make the fudge frosting, use an electric mixer to beat the butter until smooth. Add in the cocoa powder, powdered sugar, milk, and vanilla, mixing on low until combined. Increase speed to medium and beat for another minute until smooth. If the frosting is too thick, add 1 teaspoon of milk at a time until you reach the desired consistency.
- Once the brownie layers have cooled completely, place one layer onto a cake plate and top it with half the frosting (and sprinkles if using). Add the second brownie layer on top, followed by the rest of the frosting and sprinkles.
Notes
- Let the brownie layers cool completely before assembling, otherwise, the fudge frosting might melt right off!
- I recommend ensuring your ingredients are at room temperature before starting, especially your eggs.
- Make sure to measure your flour correctly! While we want the brownie layers to be cakey, we don’t want them to be dry and make your brownies crumbly.
- These are my favorite sprinkles to use!
Nutrition
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bridget says
my husband doesn't like cake (??? i know??) so I made him this for his bday this year and he was obsessed. we ate it all in 2 days between the two of us. thanks for this recipe!!
Kelly Hamilton says
I love that he enjoyed this cake for his birthday! Thanks for trying it out, Bridget.