Soft peanut butter cake layers, crunchy Butterfinger filling, and creamy chocolate peanut butter buttercream make this Butterfinger cake a dream for chocolate and peanut butter lovers!
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One of my most vivid Halloween memories is of being 7 and asking my mom to inspect my candy for razor blades (because I was that kid) and her telling me it all looked fine except the Butterfingers, which she needed to confiscate.
I knew she was full of it but let her keep them anyway—it was the Snickers I really cared about. As I’ve grown, though, I’ve come to appreciate the Butterfinger for all its chocolate-and-peanut-butter deliciousness. Can one really go wrong with those two flavors?
No need to respond. The answer is clearly NO! In ALL CAPS. With that in mind I bring you this Butterfinger cake, an ode to one of my favorite candy bars. (After Payday and Snickers. And anything shaped like an Easter egg.)
Three layers of peanut butter cake sandwiching creamy, crunchy, Butterfinger-y filling and all of that topped with chocolate peanut butter buttercream. I ate way more than my share, gave away the rest, and now wish I’d kept just a smidge for myself to satisfy my afternoon sugar cravings.
So obviously I’ll be making another one of these soon. And I think you need to make one for yourself! Because I most likely will not be sharing this one. (OK, if you show up at my house I’ll share. Especially if you come bearing coffee.)
Why you’ll love this Butterfinger cake
- No need to break out the stand mixer! You can use a handheld mixer for this one
- It’s simple to make and doesn’t require any special skills
- It’s a great way to use up leftover Halloween candy!
Peanut butter cake, step by step
Start by combining water, butter, vegetable oil, and creamy peanut butter (don’t use natural pb!) in a saucepan. Heat until the butter and peanut butter have both melted and the mixture is smooth. Set that aside to cool for a few minutes.
Meanwhile, combine your dry ingredients (including the sugar) in a large mixing bowl and beat briefly to mix. Add eggs, sour cream, milk and vanilla.
Beat that until the batter is smooth, then add the cooled peanut butter mixture—the peanut butter doesn’t need to be cold or anything; it just needs to have cooled down enough that you don’t scramble your eggs when you add it.
Beat that until smooth and divide between 3 8-inch round cake pans that have been sprayed with cooking spray AND lined with parchment paper.
Note: The second time I made this cake I was being lazy and didn’t line my cake pans with parchment. HUGE MISTAKE. Don’t be like me. Use the parchment so your cake layers come out of the pans intact.
Bake for about half an hour, then let the cake layers cool before proceeding with the recipe.
Butterfinger filling, step by step
The filling for this Butterfinger cake is so easy it’s ridiculous. It’s just a standard American buttercream with chopped up Butterfingers mixed in.
Combine butter, powdered sugar, a little milk, and some salt and beat until smooth. Add some chopped Butterfingers (from about 4 1/2 ounces of candy) and mix with a spatula to combine. That’s it. Set aside and make your frosting!
Chocolate peanut butter frosting, step by step
Beat unsalted butter and creamy peanut butter (again, don’t use natural) in a large mixing bowl until smooth.
Add cocoa powder and beat to combine. Add powdered sugar, milk, and some salt and beat until the frosting is smooth; don’t forget to scrape down the sides and bottom of the bowl periodically. And now you’re ready to assemble your Butterfinger cake. . .
Assembling your Butterfinger cake
Use a pastry bag and a large round tip to pipe a circle (or two) of frosting around the perimeter of one of your cake layers. Spread half of the filling into an even layer inside the circle; I like to use a small offset spatula for this.
Top with another cake layer, another circle of frosting, and the rest of the filling. Top with the final cake layer and frost the cake with the remaining chocolate peanut butter buttercream.
Baker’s tip: If you don’t have pastry bags and tips, you can just spread the filling over the cake layer without going all the way to the edge. This will prevent the filling from leaking out into the final coat of frosting; I just like to have some frosting inside the cake layers to act as a buffer and hold the filling in.
To decorate my cake, I used the same large round tip mentioned above to pipe dollops of frosting around the top of the finished cake. I also pressed chopped Butterfingers into the sides of the cake—I love covering a cake with sprinkles/cookie crumbs/candy/nuts because it hides any imperfections in the frosting. But decorate yours however you want! No matter what, your Butterfinger cake will be delicious.
Just don’t be surprised when you eat too much. . .and then have a moment where you never want to see another slice of cake. . .and then five minutes after that eat too much all over again.
I’m telling you: Butterfinger cake is highly addictive! Fair warning.
Did you make this Butterfinger cake? That’s great! Let me know what you think with a comment and a rating below. And post a pic on Instagram! Tag @theitsybitsykitchen so I can see! And like IBK on Facebook and follow on Pinterest for more delicious recipes.
Butterfinger cake combines peanut butter cake layers, Butterfinger filling, and chocolate peanut butter frosting to make a delicious chocolate-y and peanut butter-y cake!
- 1 cup water
- 1/2 cup unsalted butter
- 1/2 cup vegetable oil
- 1/2 cup creamy peanut butter don’t use natural
- 2 cups all-purpose flour
- 2 cups granulated sugar
- 1 teaspoon baking soda
- 3/4 teaspoon salt
- 1/2 cup full fat sour cream
- 3 tablespoons whole milk
- 2 large eggs
- 1 teaspoon vanilla extract
- 1/2 cup unsalted butter at room temperature
- 3 cups powdered sugar
- 3 tablespoons milk or heavy cream
- 1/4 teaspoon salt
- 3/4 cup finely chopped Butterfingers from about 4 to 4 1/2 ounces of candy
- 3/4 cup unsalted butter at room temperature
- 1/4 cup creamy peanut butter don’t use natural
- 1/2 cup cocoa powder
- 1/4 teaspoons salt
- 5 to 8 tablespoons milk or cream
- 4 to 4 1/2 cups powdered sugar
- Additional chopped butterfingers for garnish
- Preheat the oven to 350 degrees. Spray 3 8-inch round cake pans with cooking spray and line the bottom of the pans with parchment. Spray the parchment with cooking spray and set pans aside.
- Combine the water, butter, vegetable oil, and peanut butter together in a medium saucepan set over medium heat. Cook, stirring often, until peanut butter and butter are melted and mixture is smooth. Remove from the heat and let cool while you continue with the cake.
- Combine the flour, sugar, baking soda, and salt together in a large mixing bowl and beat with an electric mixer to combine. Add the sour cream, milk, eggs, and vanilla and beat on low speed until combined.
- Add the cooled peanut butter mixture and beat on low until batter is smooth, stopping mixer to scrape the sides and bottom of the bowl several times. Batter will be fairly thin.
- Divide batter evenly between the prepared pans and bake for 29 to 35 minutes, until a cake tester inserted into the center of the pans comes out clean.
- Cool cake layers in the pans for 30 minutes, then carefully invert onto a wire rack to cool completely before filling and frosting.
- Combine the butter, powdered sugar, milk, and salt in a medium mixing bowl and beat with an electric mixer on low speed until combined. Increase the speed to medium and beat until smooth. Use a rubber spatula to fold in the chopped Butterfingers.
- Beat the butter and peanut butter in a large mixing bowl with an electric mixer until very smooth. Add the cocoa powder and salt and beat to combine.
- Add 5 tablespoons of the milk and 4 cups of the powdered sugar and beat on low to combine, then increase speed to medium and beat until smooth. Add more milk if frosting is too thick and more powdered sugar if frosting is too thin.
- Place one layer on a cake stand or cardboard cake circle.
- Transfer about a 1/2 cup of frosting to a pastry bag fitted with a large round tip and pipe a circle of frosting around the perimeter of the cake. Use an offset spatula to spread half of the filling into an even layer inside the circle of frosting.
- Top with another cake layer and repeat the filling process. Top with the remaining cake layer. Frost your cake and decorate with additional chopped butterfingers if desired. Serve.
- Don't skip lining your pans with parchment! Even with cooking spray, the cake layers will stick!
- If you don’t have pastry bags and tips, you can just spread the filling over the cake layer without going all the way to the edge. This will prevent the filling from leaking out into the final coat of frosting.
Cake layers adapted from Allrecipes.com