Today I give you, my favorite cake: the Ultimate Chocolate Peanut Butter Crunch Cake. Of all the cakes I’ve loved – THIS is the one to have stolen my heart and run away with it. She gets me all swoony and dramatic, this cake, and I am so confident that you guys will enjoy it as much as I do. Unless, that is, you dislike chocolate. Then I can’t make any promises, but I still say you should try it. You just never know when something might turn you …

I’ve talked here before about how I was born with an allergy to chocolate. Gasp! The horror. So unfair and terrible, right? But I busted right through that little hurdle, sampling and tasting various chocolatey things until there was nary an allergic reaction in site. Now, I don’t actually recommend this approach to anyone, particularly if your allergy happens to be life-threatening (mine was not) but it seemed to have totally worked for me – that persistence and determination paid off in the most delicious way. If it hadn’t been for my sheer bravery (read: carelessness and mild stupidity) and my willingness to just throw caution right into the wind, I may very well have lived years and years of my life without any chocolate at all.

But no. One day, while traveling somewhere along the road of my childhood, I stopped to let chocolate in for a ride. It was a brownie, in fact, and it was very much against my better judgement (I was a kid, though, so there’s that). Go big or go home, right? I indulged in this brownie, sure that I’d pay for it later. But nothing happened. I was fine. Totally free and void of any and all allergic reactions (the gory details of which I will spare you here). It seemed that I had beaten that allergy after all. Poof! It was gone … Like it was all just a bad dream.

Okay fine. I didn’t technically beat the allergy – you can’t do that, right? I just grew out of it. I suppose it really just beat itself, bless its heart. But I didn’t give up on the hope that one day I’d be able to eat all the chocolate things that my heart desired, and as fate would have it, that hope actualized or materialized or, whatever you’d like to call it – it came true.

Okay, back to the cake at hand. My “Ultimate Chocolate Peanut Butter Crunch Cake” (did you read that with a deeply booming and dramatic voice?) is essentially my recreation of one of my favorite cakes at the beloved Indianapolis bakery, The Cake Bake Shop. This place makes the best cakes I’ve ever had that weren’t made in someone’s home, and I have to keep myself to a minimum number of visits per year or I’d be in trouble. They are SO good at what they do.

Now, I genuinely believe that there is a special sort of magic to homemade, from-scratch cakes that is almost never achieved by professional bakeries. Sure, bakeries can construct unbelievably beautiful, towering confections that are truly sights to behold. But when it comes to flavor, a homemade, single-batch cake is almost always going to be better. It’s just the way it is. The Cake Bake Shop’s cakes are the closest you’re going to get to that magical homemade goodness, while also being insanely good looking, and this is why it’s my very favorite bakery in this land … in your land, in my land … in all of the lands.

I’ve created a version of their chocolate peanut butter crunch cake that is utterly doable for the home cook. The recipe reads really long, guys, I realize this. But I like to fully explain things so the whole process is clear, and easily understandable. Also, you don’t have to make all of the components to this cake. You can simply prepare the cake and frosting and leave it at that. It will still be the best chocolate cake ever.

I’ll roadmap the whole thing for you here:

• My Midnight Magic Cake works as the base, and it’s essentially a black-as-night, one-bowl dark chocolate cake that is unreasonably moist and delicious (apologies to those of you who don’t care for the “m” word. It’s just the best way to describe a cake, you know?) Also, why make a two-bowl cake when you can do it in one with extraordinary results? Important questions, these are …

• The peanut butter Swiss meringue buttercream is easy and foolproof – promise. Swiss meringue buttercream, unlike traditional American buttercream, is made by heating sugar and egg whites to 160 degrees F and then whipping them up into a frothy meringue. You gradually add softened butter (lots of it) to the meringue and once it’s all in, you wind up with the fluffiest, light-as-air frosting imaginable.

• A good thing to keep in mind when making Swiss meringue buttercream is to not give up until you’ve added all of the butter. Somewhere along the way, as you’re adding in the butter, your frosting will probably start to look very thin and almost broken. But fear not! Just trust the process and keep adding that butter. Once it’s all in, it will transform into a thick, rich frosting fit for any cake with which you choose to pair it.

• The ganache layer. This is technically optional, as you can absolutely make this cake with just the cake itself and the frosting and call it a day (it will still be a delicious day). BUT! This easy, two-ingredient ganache adds an element of “special” to the cake and its density provides a nice contrast between the airy cake and the whipped frosting. It’s nice to have different textures going on in a cake. Which now leads me to …

• The chocolate crunch! This was the hardest part of the cake to crack for me, as I’m not sure what The Cake Bake Shop uses for their crunch. (Is it made in house? Do they special order the little crispy bits?!) But, in the name of accessibility and ease of recreation for you, my fellow home cooks, I’ve opted to not even ask them, and I created my own version here. Guys, it’s just chocolate covered Rice Krispies. Two ingredients. Simple! I tested the cake by adding these crispies between the layers, but found that they still softened just a bit (the moisture from the frosting is the culprit there). SO! I just pile them on top of the cake right before serving, along with some toffee and call it good. You still get the crunch without having to worry about anything getting soft and sad. Problem solved.

Alright then. I’m going to share the actual recipe now, it’s time. I need to turn my rambles off and leave you with what I think is the best chocolate cake ever. For some solid tips and caking advice, be sure to check the notes at the end of the recipe. The hints are helpful! And with that, happy baking guys.

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The Ultimate Chocolate Peanut Butter Crunch Cake

My favorite, go-to, one-bowl chocolate cake recipe makes two perfect 8-inch cakes. But! I personally like the way a three-layer cake looks, so I simply slice one of my cakes in half, creating a taller, more impressive-looking cake, and giving you more surface area to cover in frosting.

The cake layers here are a riff on Robyn Stone’s (Add a Pinch) chocolate cake recipe. Also, please note that you will need a candy thermometer to make the buttercream.

Course Dessert

Author Harvest & Honey

Ingredients

• 2  cups  all-purpose flour
• 2  cups  sugar
• 3/4  cup  unsweetened dark cocoa powder such as Hershey’s Special Dark
• 2  tsp baking powder
• 1 1/2  tsp baking soda
• 1  tsp salt
• 1  tsp espresso powder
• 1  cup  buttermilk
• 1/2  cup  vegetable or canola oil
• 2  large eggs
• 3  tsp vanilla extract
• 1  cup  boiling water
• 1 cup chocolate-covered toffee bits such as Heath (optional)

Peanut Butter Swiss Meringue Buttercream

• 8 egg whites
• 2 ¼ cups granulated sugar
• ¼ tsp salt
• 6 sticks (3 cups) unsalted butter at room temperature
• 3 tsp vanilla extract
• 1 cup creamy peanut butter
• Candy thermometer special equipment you can purchase right in the baking aisle

Chocolate Ganache (optional)

• 10 ounces semi-sweet chocolate chips I use mini
• 1 cup heavy cream

Chocolate Crunch (optional)

• 1 cup Rice Krispies cereal
• ½ cup melted semi-sweet chocolate from about 1/2 to 2/3 cups chips

Chocolate Glaze (optional; for decorating the top)

• 2.5 ounces chocolate chips semisweet
• 3 Tbsp butter

Instructions

To make the cake:

1. Preheat your oven to 350º F. Grease and flour two 8-inch cake pans.
2. Combine the flour, sugar, dark cocoa, baking powder, baking soda, salt, and espresso powder in a large bowl or in the bowl of a stand mixer. Whisk or mix (with the whisk attachment) to thoroughly combine.
3. Add the buttermilk, oil, eggs, and vanilla to the dry mixture and mix everything together on medium speed, using the whisk attachment, until well combined. Reduce the speed and carefully add the boiling water to the cake batter, mixing just until well combined (make sure to scrape the bottom of the bowl to ensure everything is mixed all the way down.

4. Divide the batter evenly between the two cake pans. Bake for 30-35 minutes, until a cake tester inserted in the centers comes out clean. Remove the cakes from the oven and allow them to cool in the pans for at least 20 minutes before removing and transferring them elsewhere to cool completely.

5. When the cakes are cool, slice one of them in half horizontally through the center with a long, serrated knife. This will give you three cake layers.

6. To assemble the cake:

7. Place a cake layer down on your cake stand and spread it with a layer of ganache. Next, spread a thick layer of buttercream over top and then sprinkle with some of the toffee (if you're using toffee). Add another cake layer and repeat the same process (ganache, buttercream, toffee). If things are very soft on you right now, you can always pop the cake in the fridge for 20 minutes or so, to allow the ganache and frosting to firm back up for you.

8. Place the final cake layer on top and frost with a thin layer of buttercream, covering the top and sides. I like to drag my inverted spatula (or whatever frosting implement I’m using) across the entire surface, scraping any excess frosting and ganache away as I go, and creating a smooth cake surface. Pop the cake in the fridge for 30 minutes. This will be the “crumb coat.”

9. After 30 minutes, finish frosting the cake by smoothing a nice, thick layer of buttercream all over the top and sides of the cake. Top with the chocolate glaze, allowing it to spill over the sides. Sprinkle with some of the chocolate crunch, and some extra toffee, if you like.

To make the buttercream

1. In the bowl of a stand mixer fitted with the whisk attachment, combine the egg whites, sugar, and salt. Mix until well combined.
2. Place a small pan with about an inch of water on the stove over medium-heat. Place the mixing bowl with the egg white mixture over the pan with water, ensuring that the bowl doesn’t actually touch the water (you’ve made a double boiler!).

3. Gently heat the mixture to 160 degrees F, stirring frequently with a rubber spatula so the whites don’t cook and the sugar doesn't stick to the sides of the bowl. Once you’ve reached 160 degrees, transfer the bowl back to the mixer and mix (with the whisk attachment) until you get stiff peaks, about 8 to 10 minutes. The bowl should have cooled to room temperature by the time you’re done with this step.

4. Now, with the mixer on medium speed, add the soft butter, about 2 Tbsp at a time, to the meringue until you’ve used it all up. If you find that it’s looser than you'd like, just pop the bowl in the fridge for about 20 minutes and that should do the trick.

5. Add the vanilla and the peanut butter, and mix until combined. I like to store the buttercream in the fridge until I frost the cake.

To make the ganache (optional)

1. Place the chocolate chips in a bowl. Heat the cream in a small saucepan over medium heat just until it barely simmers. Pour the hot cream over the chocolate chips and stir until the chocolate is fully melted and the mixture is smooth and creamy. Pop the bowl in the fridge until the ganache is thick and fudgy (you want it spreadable, but not loose and runny); about 25 to 30 minutes.

To make the chocolate crunch (optional)

1. Spread the krispies out on a baking sheet that has been covered with either parchment paper or a silicone baking mat. Drizzle the melted chocolate over top and stir to fully coat the cereal. Feel free to add more chocolate, if needed. You want the cereal completely covered. Allow the mixture to fully harden before using it to top the cake (I put it in the fridge).

To make the chocolate glaze (optional)

1. Combine the chocolate chips and the butter in a small saucepan over medium heat. Warm just until the butter and chips have melted, creating a glossy, smooth glaze. Cool to room temp before drizzling over the cake. If it gets too firm to drizzle, just warm it for a few seconds in the microwave, and add a little extra butter, if needed.

Recipe Notes

Cook’s Notes:

I find it helpful to bake the cake the night before. Then all you have to do the next day is whip up the buttercream (which takes about 20 minutes); and the crunch and ganache (both of those two things take 5 minutes to make). 

It is also helpful to leave the butter for the frosting out overnight, so you get a true "room temperature." I don't always think ahead enough to do this, but when I do ... man am I proud of myself. 

The cake batter will be thin after adding the boiling water. This is totally fine and what you want.

Freezing instructions: Let the baked cake layers cool completely. Wrap them well with plastic wrap and then with foil. Put each layer into a freezer bag and freeze up to 2 months. To serve, thaw in the refrigerator overnight. The next day, the layers are ready to fill and frost.