Peanut Butter Banana Cake

This cake left me heartbroken in my first attempt. How so? Look.

My cake collapsed in a heap!

This recipe is created by Cheng Yi, the man behind Fatboybakes, who happens to be a civil engineer by training. He has been quoted as saying that mixing batter was not much different from mixing concrete. I would think that with an engineer behind this creation, all structural issues would have been ironed out.

What a mess!

As it turned out (obviously!), the collapse of this cake was all my fault (of course!). I am no engineer, I tell you. I used to get headaches during physics. 

This cake is built layer by layer. It starts with a crushed Oreo biscuit base followed by a mixture of peanut butter and whipping cream, sliced bananas, whipped cream, chocolate sponge cake, whipped cream and then finally topped with ganache.



As we all know, the stability of a structure lies in its foundation. In this case, the foundation is the layer of bananas and creamy peanut butter and whipping cream. The bananas = bricks and the peanut butter/whipping cream = cement, if you will. Now I am starting to think like an engineer. 

Peanut butter and whipping cream. I could
just scoop this with a spoon. Noms!

In my first attempt, I laid only one layer of bananas. Why? Because I had no idea that I needed more than a layer (non-engineering brain at work here). Besides, I bought only 3 Cavendish bananas (because I couldn't get pisang mas or berangan). Two I used for the cake and one I walloped on the spot. No wonder I was short of bricks :D



Assembling the cake is not too bad even if you are seriously lacking in finesse like me. The bottom layer is an Oreo biscuit base. You use crushed Oreos, filling and all, which is mixed with melted butter. Yes, just like making a cheesecake base. I was apprehensive about including the Oreo filling because it might be too sweet. But my worries were unfounded as I used no-sugar added peanut butter.

Now on to the "cement"'. The peanut butter and whipping cream are beaten to form a creamy and firm mixture. I knew I was going to have whipping cream flying into my face and I was right. Look at the mess. No, I did not do  a selfie of my face spotted with whipping cream. It was not a pretty sight.

Whipping cream flew everywhere.

Next, simply dump this peanut butter/whipping cream onto the Oreo base. Easy, right? After that, arrange sliced bananas on the creamy mixture. This is where I got it wrong. Tell you about it in a bit.

Must press the bananas into the peanut butter
mixture and then lay another layer of bananas.

Then a layer of whipped cream goes on top of the bananas. Next, lay a piece of sponge cake on top.

Then the remaining whipped cream goes on top of the sponge. At this point, I chilled the cake and went on to make the ganache. When that was cool enough, I poured the ganache onto the cake, tilting the pan to evenly coat the top of the cake with the melted chocolate.  The cake goes back to the fridge to chill for a few hours. 

My problem started when I sliced the cake. Gosh! It simply collapsed when my knife cut into it. It was all wobbly and couldn't hold its shape. Sheeeshh... This was how my first slice turned out.

What a flop!

I simply couldn't get over the disaster. I thought about this cake for the remainder of the day and the day after. Think, think, think. Then I got it. The problem was :

1. Not enough bananas = poor foundation (not enough bricks);
2. The sliced bananas should be pushed into the peanut butter/whipping cream layer; and
3. The cake should have been chilled a lot longer (overnight) in order for the peanut butter/whipping cream to set further (The cement wasn't fully set).

But as far as taste was concerned, that ugly blob of a cake was sheer bliss. It was like eating ice-cream, simply heavenly!

I was very determined to redeem myself and do justice to this fabulous recipe. I had to make this cake again and make it better! And so I did. The second time, I had 2 layers of bananas and the cake was chilled overnight. The result? Tadaah...

Now, let me give a short review on the recipe which was published in the Nutriplus cookbook, Thinking Out Of The Shell.

Cheng Yi's recipe looks simple and doable but there are many technical issues which are not spelled out for you. Obviously, if the recipe tells you all there is to know about assembling this cake perfectly, it will spill over to 2 or 3 pages long.

Then people will complain that the recipe is "cheong hei" (long winded). And seriously, from now onwards, I will not complain if I see a "cheong hei" recipe.

This is a very stable structure.

So when following a recipe, use your instincts - baking, engineering or otherwise. My main mistake was not pressing the banana slices into the peanut butter/whipping cream. The one layer of banana was basically floating on the layer of cream. That made for a very weak foundation which could not support the weight of the cake. 

I also learnt that the sequence of steps presented in a recipe need not be strictly followed in certain circumstances. For example, this recipe tells you to make the peanut butter/whipping cream mixture first and then whip the remaining whipping cream.

I find it more practical to whip the remaining whipping cream first. Why? That way you need not clean your cake mixer before beating the peanut butter/whipping cream mixture. Even if you have 2 cake mixers, why do extra work?

You will need a sponge cake for this cake and though the recipe calls for Sponge Mix, I did not use that because I did not have any. Instead I baked my own sponge cake.

With my third attempt at this cake, I can now share with you my tips for making this cake successfully. 

The detailed instructions will be denoted in red so that you may skip the "cheong hei" parts because I will sound like an old auntie telling you long grandmother stories.

Peanut Butter Banana Cake
Recipe source : Fatboybakes as published in Thinking Out of the Shell (page 23)
Note : I have included my notes in red for my future reference and to share some tips.

Ingredients :
- 1 packet Oreo biscuits (137g)
- 30g melted butter
- 250g chunky peanut butter (I used no sugar added)
- 600g whipping cream
- 4-5 ripe bananas, perferably pisang mas

Sponge Cake
- 125g chocolate sponge mix
- 2 eggs
- 25ml water
- 25ml melted butter
Note : I did not use a sponge mix but baked my own.

Ganache
- 150g Dark Chocolate (broken into small pieces)
- 150 cream (I used cooking cream. Can also use whipping cream)
- 10g butter (my addition)

Method :
1. Grind the Oreo Biscuits together with their fillings in a food processor until fine. (I just bashed them up in a plastic bag). Add melted butter and combine well.
2. Press mixture into the bottom of an 8" round tin with a removable base.
3. (I do step 6 first before proceeding to steps 3, 4 and 5)) Place peanut butter and 240g whipping cream in the bowl of a mixer. Whisk until the mixture is light, fluffy and firm. (I placed the peanut butter in a mixing bowl and drizzled the whipping cream into the bowl while whisking the peanut butter. This prevents the whipping cream from flying everywhere).
4. Spread the mixture over the biscuit base. (I poured the whole lot onto the biscuit base and used the back of a spoon to spread the mixture).
5. Slice the bananas and lay over the peanut butter layer. (After laying the first layer, gently press the banana slices into the peanut butter layer. Then lay the second layer of bananas on top. Press to make sure that your banana layers are compacted into the peanut butter layer).
6. Whip the remaining whipping cream until stiff peaks form. Be careful not to overbeat. (I do this as step 3 and set the whipped cream aside in the fridge before proceeding to beat the peanut butter at steps 3, 4 and 5).
7. Lay a layer of the whipped cream to cover the bananas. (You want enough cream to cover the bananas. Use more here than at the end. Use the back of a spoon to spread the cream).
8. Lay a layer of the sponge cake on the cream.
9. Spread the remaining cream over the cake, and pour over the cooled chocolate ganache (After spreading the cream on the cake, I placed the cake in the fridge. Then I made the ganache. When the ganache was cool enough, I poured it over the chilled cake. To spread the ganache, tilt the pan).
10. Refrigerate for a few hours (It is best to refrigerate overnight).

To make the sponge :
1. Place sponge mix, eggs and water into the bowl of a mixer and whisk until thick and pale.
2. Add butter and mix a little bit more until incorporated.
3. Pour into a lined 8" round tin and bake at 170C for 15 minutes or so.
(I baked my own chocolate sponge cake from scratch).

To make the chocolate ganache :
1. Bring the cream to a boil.
2. Pour the hot cream over the dark chocolate and leave to sit for a few minutes (5 minutes).
3. Stir the chocolate mixture which should form a glossy ganache.
Note : I placed the chocolate and butter into a glass measuring jug to make it easier to pour the ganache)

This post is linked to the event, Little Thumbs Up organised by Zoe of Bake for Happy Kids and Doreen of My Little Favourite DIY and hosted by Faeez of BitterSweetSpicy.

This post is also linked to Cook-Your-Books #21 hosted by Joyce of Kitchen Flavours.