Put your party pants on, because this is a party cake! I am super excited to be sharing the recipe for this dude - it comes from the newest book from Brian and Bake From Scratch! Each year they put together an incredible compilation of all the recipes from the last year, and turn them into one big, beautiful book. I have a couple of recipes in there from my contribution to the holiday cookie issue last year - it’s always so, so exciting to see my photographs in print alongside some of my fave bakers and bloggers. The book is such a lovely round up, but also an amazing idea if you live outside of the States and want all the recipes that were included this past year, rather than having to get the magazine sent overseas each month!
When I was choosing something to make (with the assistance of Brooke and Brian via facetime while they had cocktail hour in their hotel), I was looking for something a wee bit epic. I went back and forth for a bit, before Brian suggested I take a bunch of recipes from their layer cake section, and mix and match them. There’s a super cool section at the start of the cake chapter that has a whole lot of cake recipes, and a whole lot of buttercream recipes, and you can essentially just pick a cake, pick a buttercream, and you have an instant combination. It’s such a clever idea - I’ve highlighted two of the cake recipes here and two of the buttercreams, but there are a whole load more in the book! Definitely pick up a copy if you can - it would make the most amazing present for the baking enthusiast in your life!
I couldn’t go past the classic peanut butter and chocolate combination for this cake. I made both the chocolate and the peanut butter cakes - both are stir together cakes (rather than needing a mixer), so come together super quickly. I made them the night before, then once they were cool, wrapped them up tightly and popped them in the freezer overnight - ideally if I have the time, this is my favourite way to frost a cake, but room temp or chilled cakes work great too! I then stacked them up, alternating not only the cake flavour, but the buttercream filling inside, which made for a super exciting cake interior.
I’m not usually a huge fan of American Buttercream (We all know I am a die hard German buttercream girl), but there are a two times when I absolutely love it: when it has peanut butter, and when it has chocolate. I used both of these to finish off this cake, both from the mix and match section I mentioned - I crumb coated it using both flavours, then couldn’t help but finish it off in a way that’s my ultimate go to, blobs of buttercream piped on using a french star tip. I was going to just do a sparse covering of the buttercream blobs, but always end up getting carried away (they are so, so fun), so covered the whole thing, which I’m super happy I did, as it ended up being the most perfect cake:buttercream ratio!
This cake looks super fancy but I promise that it is much easier than it looks - it’s two batches of cake, but both come together super easy, and bake up amazingly flat, with no levelling required. Then it’s just two quick batches of buttercream which you use to fill and crumb coat the cake, then transfer the remainder into your piping bags and blob away! I wanted to have three colours of buttercream so I mixed together some of the chocolate and peanut butter (I actually used the frosting that got scraped off in the crumb coating process), to give me a light brown choc peanut butter buttercream too, which worked so perfectly! This cake would be the most amazing thing to take to a celebration or for a birthday - it’s the perfect texture, and the flavour combination is just incredible.
A few wee tips:
- I almost always add more heavy cream to american buttercream to get it to the texture I want - you want something smooth and silky that is going to be really nice to pipe, so I often add up to about a ¼ cup more than the recipe calls for. Once you have mixed up the buttercream, just keep adding heavy cream until it is a nice soft smooth texture, then crank up the speed of the mixer and let it go on high for a few minutes to make sure it is super fluffy.
- Once I have the buttercream super fluffy, I then like to turn the mixer to low and let it go for a minute or two, just to help get rid of any big air pockets which will make bubbles when you’re frosting the cake.
- I ended up with a wee ombre crumb coat situation which I kind of loved - to get this, I plopped some peanut butter buttercream in a piping bag, then a little chocolate, another scoop of peanut butter, then a big scoop of chocolate, then snipped the end off the bag and used that to cover the cake on the turntable. I then smoothed it off, and used any excess to fill in holes and to do the top. The ombre was a happy accident, but I will be definitely be doing it this way again!
- As you can see in the photos I didn’t worry toooo much about making the cake super flat on the top or getting the edges super sharp, because I knew that I was going to be covering it in blobs of buttercream.
- When I’m making two cakes in a row, I usually cool the pan quickly by running it under cold water when I wash it - this means you can get your second cake on the go as soon as you can!
Made this recipe and love it?
If you made this recipe then I would LOVE for you to leave me a review below to let me know how you liked it! Also, please make sure to tag me on Instagram if you make it!
A note on salt and oven temperature
It is important to note the type of salt that is called for in a recipe. I use Diamond Crystal salt throughout my recipes - if you use a different sort of kosher salt or regular table salt you will need to adjust accordingly as some salt is 'saltier' than others. Morton's salt is twice as salty, so you will need half the quantity. Same goes for a regular table salt. I am working to get gram measurements throughout my recipes for salt but still getting there.
All oven temperatures are conventional unless otherwise stated. If you are baking on fan / convection, you will need to adjust the temperature. An oven thermometer is a great investment to ensure that your oven is the correct temperature.
Tools and equipment
For a list of my go-to tools and equipment, I have a post you can refer to here.
Why is this recipe in grams?
I post my recipes in grams as it is the most accurate way to bake. Cups are not only inaccurate but they vary in volume worldwide. There is no way for me to provide one cup measure that works for everyone. However, posting in weight fixes this issue. If you would like the recipe in cups you are welcome to convert it yourself via google, but please do not ask me to do it for you as I am not comfortable providing a recipe using a method that I have not tested. Baking with a scale is easy, accurate, and also makes cleanup super simple. Here is the scale that I use if you would like a recommendation! Here's to accurate baking! If you would like to scale this recipe or convert for another pan size, use my calculator!
Print
Chocolate and Peanut Butter Layer Cake with Chocolate and Peanut Butter Buttercream
- Yield: Makes One Eight inch, four layer cake
Description
Chocolate and Peanut Butter Layer Cake with Chocolate and Peanut Butter Buttercream
Ingredients
Chocolate Cake
- 133g granulated sugar
- 150g light brown sugar
- 55g canola oil
- 1 large egg, room temperature
- 1 large egg yolk, room temperature
- 1 ½ tsp vanilla extract
- 210g all-purpose flour
- 50g unsweetened cocoa powder
- 1 ¾ tsp baking powder
- ¾ tsp kosher salt
- ½ tsp baking soda
- 240g whole milk, at room temperature
- 160g hot coffee
Peanut Butter Cake
- 220g light brown sugar
- 85g peanut butter (use regular, smooth packaged peanut butter - natural will separate)
- 75g vegetable oil or other neutral oil
- 2 large eggs, room temperature
- 1 tsp vanilla extract
- 185g all-purpose flour
- 2 tsp baking powder
- ½ tsp plus ⅛ tsp baking soda
- 1 tsp kosher salt
- 240g buttermilk, at room temperature
Chocolate Buttercream
- 350g unsalted butter, at room temperature
- 130g unsweetened cocoa (I used dutch process)
- 720g powdered sugar, sifted
- 2 tsp vanilla
- 1 tsp kosher salt
- 90g heavy whipping cream, plus more as needed (see notes)
Peanut Butter Buttercream
- 255g unsalted butter, at room temperature
- 130g smooth peanut butter
- 810g powdered sugar, sifted
- 1 tsp salt
- 135g heavy cream, plus more as needed (see notes)
Instructions
CHOCOLATE CAKE
- Preheat the oven to 350°f / 180°c. Butter and flour two 8” round cake pans. Line bottom of pans with parchment paper.
- In a large bowl, stir together the sugars and oil. Add egg, egg yolk, and extract, and stir to combine.
- In a medium bowl, sift together flour, cocoa, baking powder, salt, and baking soda. Gradually add flour mixture to sugar mixture alternately with milk, beginning and ending with flour mixture, stirring just until combined after each addition. Stir in the hot coffee just until combined. Divide batter between cake pans.
- Bake until a wooden pick inserted in the center comes out clean, 25 to 30 minutes. Let col in pans for 10 minutes. Remove from pans and allow to cool on a wire rack completely. If preparing ahead, once cool, wrap tightly in plastic wrap and freeze overnight.
PEANUT BUTTER CAKE
- Preheat the oven to 350°f / 180°c. Butter and flour two 8” round cake pans. Line bottom of pans with parchment paper.
- In a large bowl, stir together the light brown sugar, peanut butter, and oil until combined and creamy. Add eggs and vanilla, stirring until just combined.
- In a medium bowl, soft together the flour, baking powder, baking soda, and salt. Gradually add the flour mixture to the sugar mixture alternately with buttermilk, beginning and ending with flour mixture, stirring until just combined after each addition.
- Divide the batter between the pans (I like to do this by weight).
- Bake until a wooden pick inserted in the center comes out clean, 25 to 30 minutes. Let cool in pans for 10 minutes. Remove from pans, and let cool completely on wire racks.
- If preparing ahead, once cool, wrap tightly in plastic wrap and freeze overnight.
CHOCOLATE BUTTERCREAM
- In the bowl of a stand mixer fitted with the paddle attachment, beat the butter and cocoa at low speed until well combined. Gradually add the powdered sugar, 1 cup at a time, alternately with cream, 1 Tbsp at a time, beating until combined. Add vanilla and salt. Increase the mixer speed to medium-high. Beat until mixture is smooth, about 1 minute. Add more cream if needed (see notes), and beat on high until soft and spreadable. Reduce the mixer to low and beat for 1-2 minutes to remove any air bubbles. Use immediately, or place a piece of plastic wrap over the surface of the buttercream until you use.
PEANUT BUTTER BUTTERCREAM
- In the bowl of a stand mixer fitted with the paddle attachment, beat butter and peanut butter at medium speed until smooth. Reduce mixer speed to low. Gradually add powdered sugar and salt, beating until combined. Add cream, beating until a spreadable consistency is reached. Add more cream if needed (see notes), and beat on high until soft and spreadable. Reduce the mixer to low and beat for 1-2 minutes to remove any air bubbles. Use immediately, or or place a piece of plastic wrap over the surface of the buttercream until you use.
ASSEMBLY
- Secure one of the peanut butter layers of cake to a cake turntable using a little buttercream (I actually frosted mine on a cake stand, on top of a turntable). Add about ¾ cup chocolate buttercream onto the first layer of cake, and smooth using an offset spatula. Top with a chocolate layer, and add about ¾ cup peanut butter buttercream, and smooth down. Repeat the process, adding a peanut butter layer, chocolate buttercream, and finally a chocolate layer (I like to put the top layer upside down to make the top nice and flat, but I forgot this time!).
- Frost the cake with a crumb coat - to do this I put peanut butter and chocolate buttercream into a piping bag (see notes), and then spun the turntable while I piped the buttercream onto the outside of the cake. Don’t worry if there are some gaps. Smooth using a cake scraper or an offset spatula, scraping off the scraper between passes, and placing the scraped off buttercream into a bowl off to the side.
- Once you have crumb coated your cake, place it in the fridge to chill for about 20 minutes, while you prepare the buttercream for the outside.
- Fit three piping bags with french star tips - I use Ateco #866. If you used a bowl to the side to collect the scraped buttercream (I did, and ended up with both peanut butter and chocolate buttercream), mix well to combine, adding more chocolate or peanut butter buttercream if necessary until you have a nice light brown colour. Transfer to a piping bag. Transfer the remaining chocolate and peanut butter buttercreams to the other two piping bags.
- Remove the cake from the fridge, and pipe blobs of buttercream over the surface of the cake - I just blob them on randomly, switching colours every now and then to keep the pattern nice and mixed up. Repeat until the cake is completely covered in buttercream blobs.
- Store in the fridge until ready to serve. Once cut, store in an airtight container in the fridge.
Notes
Recipe Reprinted with permission from Bake From Scratch: Artisan Recipes for The Home Baker
Can you use Dutch process cocoa powder for the cake? I know there’s both baking powder and soda in the cake but just want to be sure!
I haven't tried it but it should be fine with the baking powder in there! 🙂
If you're looking for a cake project that is worth the effort, look no further. Yes, it's a bit of an undertaking because it's four cakes and two batches of frosting. That said, it's totally worth it. Plus, Erin's instructions are always a breeze to follow so everything is straightforward.
Something went a touch awry with the rise on my chocolate cakes that I'm almost certain was me skipping a step or reading something wrong. I'm planning to make it again to figure it out. The peanut butter ones turned out perfectly.
As for the frostings, all I can say is yum. The combo is even tastier than they are on their own. I highly encourage the baking of this cake. It's a winner.
Hiiii thank you so so much for the lovely review! I am so happy you loved it xx