Giant Reese's Peanut Butter Cup Cake

It's been a busy birthday month in the office in March and more coming up in April.  I made this for Kim who loves chocolate and peanut butter so I decided to make a giant reese's peanut butter cup cake. It's a chocolate sponge with a peanut butter frosting encased in a chocolate shell. I was really pleased at how it turned out particularly the cross section as it really does look like a giant reese's cup!

This is my first time creating a shell with melted chocolate using the giant cupcake case and I am impressed at how easy it is. I will definitely keep this in mind for decorating giant cupcakes as I always find it difficult to decorate the bottom half - I have been using chocolate fingers but this gives it a more refined finish. A tip that I read online was to heat up a frying pan and to place the chocolate shell upside down for a few seconds to get a smooth, even finish to the shell. My inspiration for this cake came from My Cupcake Addiction and you can watch the video to get more helpful tips.

 Giant cupcake case (bottom half only) & melted chocolate 

 pour chocolate into the case and tip the case at an angle, turning as you go to get a smooth covering 

 it should look like this. Place it to set in the fridge to set (at least 20 minutes) then coat with a second layer 

 You can just about see that the edges at the top are uneven 

 heat a pan then place the chocolate shell upside down and twist it slightly to get smooth, even edges 

 looks much better now! 

 I used toothpicks to mark out the cake sections. You want to discard the top bit (the uneven top) and the middle bit (this is where the peanut butter filling goes) 

 Place bottom 1/3 of the cake into the chocolate shell 

 Cover with a thick layer of peanut butter frosting. Use a palette knife to smooth the top 

 place the flat top 1/3 of the cake on top 

 cover with chocolate ganache - try not to spill over the edges 

 after it has set 

 Normal sized Reese's cup for size comparison 

 cross section of the cake 

For the cake

185g plain flour
200g caster sugar (I'd suggest 250g for a sweeter bake)
185mls buttermilk
3 tablespoons vegetable oil
2 teaspoon vanilla extract
2 eggs
1.5 teaspoon bicarbonate of soda
3/4 teaspoon baking powder
185mls warm water
95g cocoa powder

For the peanut butter filling

110g icing sugar
200g smooth peanut butter
70g butter, at room temperature
3/4 teaspoon vanilla extract
1/4 teaspoon salt
80ml double cream

For the chocolate ganache

200g dark chocolate

150g double cream

15g butter (optional) 

For the chocolate shell

200g chocolate, melted 

• Preheat the oven to 180C.
• Mix all the dry ingredients in a large bowl. 
• Add in eggs, oil, vanilla extract, buttermilk and warm water.
• Mix thoroughly.
• Divide into the cupcake cases and bake for approximately 35-45 minutes or until a skewer inserted into the centre comes out clean. (the bottom half my need more baking time than the top half) 
• Allow to cool completely before decorating. 
• To make the filling,  place the icing sugar, peanut butter, butter, vanilla and salt in the bowl of an electric mixer fitted with a paddle attachment.
• Mix on medium-low speed until creamy, scraping down the bowl with a rubber spatula as you work.
• Add the cream and beat on high speed until the mixture is light and smooth. 
• To make the chocolate ganache, heat the cream in a small saucepan until almost boiling. 
• Remove from the heat and stir in the chopped chocolates until smooth. Add in the butter if using. 
• To assemble the cake, follow the instructions that accompany the photos above or watch the video from My Cupcake Addiction.