If a peanut butter cup had a cake avatar, this would be it. I took my favourite chocolate cake batter that bakes up rich and fudgy, layered it with a creamy peanut butter frosting that’s good enough to eat as is, and then added a thin but perfect topping of chocolate ganache. It’s indulgent, celebratory but also meant to sneak bites from on any random day. Let’s make some cake!

I’ve used this same cake batter as a layer cake here and adapted it for a German Chocolate Cake too. It really is a lovely cake because the melted chocolate gives it fudginess but the yoghurt, hot water and baking soda give it lightness and moisture. It’s perfect.

This time, because I was making it for friends who love peanut butter and chocolate, the combination was something I absolutely couldn’t ignore in a cake. And while my layers weren’t the most even, no one had any complaints about that and the cake was absolutely demolished. It really is a flavour combo that can never go wrong!

This is a great cake to start one or even two days before you plan to serve it. The cake itself should be chilled before you frost it, then chilled before you add the chocolate so that the peanut butter frosting doesn’t melt, and then the whole thing sort of settles and becomes more flavourful once assembled and chilled overnight. So plan ahead!

While I do recommend eating this at room temperature, this is one of those rare butter cakes that also remains pretty moist even when cold from the fridge, thanks to all the liquid ingredients in the batter. But if you have the time, I will say again that room temperature is this cake’s best friend.

I hope you love it!

Chocolate Peanut Butter Layer Cake

Rich chocolate cake layered and topped with creamy peanut butter frosting and a chocolate ganache to finish

Prep Time: 40

Cook Time: 1

Total Time: 1 40

Makes: 8 large slices

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Ingredients

For the cake

200 gms dark cooking chocolate (70% to 75%), roughly chopped
1 and 1/2 cups all-purpose flour (180 gms)
1 tsp baking soda
1/4 tsp salt if using unsalted butter
200 gms butter, at room temp
1 and 1/2 cups soft brown sugar, light or dark (320 gms)
1/3 cup thick plain yoghurt, at room temperature (75 gms)
2 eggs at room temperature (see notes)
1 and 1/2 tsps vanilla extract
1 cup freshly boiled water (250 ml)

For the frosting

150 gms unsalted butter, at room temperature
1 cup creamy peanut butter (270 gms; see notes)
1/2 tsp vanilla extract
1 cup icing sugar (115 gms)
1/4 tsp salt
3 tbsps cream at room temperature (whipping cream preferably, regular cream is ok)

For the ganache

60 gms dark chocolate (55%), finely chopped and at room temperature
1/3 cup cream (80 ml; whipping cream preferably, regular cream is ok)

Instructions

First make the cake. Preheat the oven to 175 C and grease a 9 inch springform tin.
Melt the chocolate in a double boiler or microwave in ten second incremements, stirring between each. Set aside to cool slightly.
In a large mixing bowl, beat the butter and sugar with a hand mixer on medium speed till light and creamy. Add the yoghurt and beat on low speed to combine.
Now add the eggs and vanilla extract and beat to combine. The mixture may appear curdled but it will stabilise in the next step.
Next, add the melted chocolate, and beat briefly on low speed until just combined. It will now be smooth and thick.
Sift in the flour, cocoa, baking soda and salt (if using). Fold it all in very gently till only a few streaks of flour remain. Now add the hot water, a little at a time, to prevent any lumps forming, and continue to fold the batter with a silicone spatula. I prefer doing this step by hand as a mixer could cause the hot water to splash here and there and make a mess.
If you still see lumps (I often do, despite my best efforts), beat with the hand mixer on low speed for a few seconds until smooth. The batter is slightly runny.
Pour the batter into the prepared loaf tin and bake for 50 minutes to an hour, till a toothpick poked in the center comes out clean. The cake will dome and crack a bit. Let the cake cool completely at room temperature. The cake can be left out overnight, loosely covered and in fact, I recommend it because the texture and flavour both improve. Before you frost it, chill the cake for 1 hour.
Make the frosting. Keep in mind that this cake is not heavily frosted so feel free to double the frosting quantities if you prefer.
Beat the butter, peanut butter and vanilla with a hand mixer on medium speed, until creamy. Sift in the salt and icing sugar and beat again until smooth and thickened. Now add the cream and beat on low speed to loosen up the frosting and make it spreadable (see photos below). If needed add more cream and also taste to check if you need more sugar.
If the frosting seems a bit soft (especially if it's a warm day), refrigerate it for about 15 minutes to let it firm up but still be spreadable.
In the meantime, even out the top of the chilled cake by slicing off the domed portion. Now slice the cake horizontally in two. Lift the top half off carefully and set aside. Spread half the frosting on the bottom half, then gently place the top half back on it, and frost the top as well. Spread the frosting to the sides and over the edges and smoothen it out.
Refrigerate the cake for 30 minutes to an hour to let the frosting firm up but not harden completely. This chill time is necessary, otherwise when you add the ganache, it's like to get a little messy on the top.
To make the ganache, place the finely chopped chocolate in a bowl and gently heat the cream on the stove till warm and barely simmering, definitely not boiling. Pour over the chocolate and let it sit undisturbed for about 5 minutes. Stir gently to melt down the chocolate into a smooth and runny ganache. Let this rest at room temperature to thicken further until no longer warm but still spreadable. You can refrigerate it but I find it gets a bit too thick that way and while the frosted cake chills, you can just let the ganache sit out and thicken.
Finally, pour the ganache over the top of the chilled cake spreading it to the edges and letting it drip gently over. Let the cake set at room temperature for about 15 minutes or refrigerate for about an hour to firm up the ganache, and then slice. While I love digging in immediately while the ganache is creamy, the cake actually tastes better after a bit of a chill, and if you can wait, the next day!
Store in the fridge for 5 to 6 days and in the freezer for about a month. Bring individual pieces to room temperature before eating. Happy baking!

Notes

Shop this recipe: Dark Chocolate, Brown Sugar, Cocoa, Baking Paper, Mixing Bowl, Hand Mixer

*I used a natural, unsweetened peanut butter here and it worked great. You can also use a processed peanut butter keeping in mind the frosting will be sweeter because processed versions contain sugar.

*Cake batter from this dense chocolate loaf and an eggless version here! However, the eggless version is a little bit fragile and I have not tried layering it. You could instead use this peanut butter frosting with this eggless chocolate cake instead.

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