4 inch peanut butter cake with chocolate fudge icing for a rainy day

While it rained the entire day on the Bank Holiday, I baked this cake with Mr. Pear. We had a slice while playing Botanicula. Both were lovely, uplifting things on such a miserable day.

Chocolate fudge peanut butter cake

I’d actually planned this cake for for his birthday earlier in the month, but the making of it went a bit wrong–through clumsiness I caused the yet-unmixed egg to catapult out of the mixing bowl onto the kitchen floor. When I managed to clean up and put everything together, the icing was weird and the layers slid about alarmingly. I pleaded with the finished, wonky, ugly cake to stay in one piece, to fulfil its destiny as a proud, upright birthday cake.

When I cut it, my sad, ill-made monster completely collapsed on itself.

Chocolate fudge peanut butter cake

But the slices I managed to save were delicious, so I tried again a few weeks later and it went quite a lot better, relatively speaking.

The cake is a little wonky but it stands up on its own. The icing is slapdash but glossy. The cake, as a whole, still looks like a mess, but it also looks like something you want to eat. It doesn’t ask you to admire how clever it is–it just says, eat me. That’s good enough, isn’t it?

Chocolate fudge peanut butter cake

Chocolate fudge peanut butter cake


Cake adapted from the Primrose Bakery’s peanut butter cupcake recipe (roughly halved), chocolate fudge icing from Local Milk.
Makes a 4-inch, 4-layer cake which yields 4 – 6 slices.
(This is a tiny cake, but it’s tall for its size and also fairly rich, it most definitely serves more than you think it will. Good for a small household or gathering.)

The cake layer itself has a rich peanut butter taste and firm yet fluffy crumb. It’s not too sweet. This contrasts with the melt-in-the-mouth, ever so slightly grainy, sweet and rich chocolate icing. Usually I prefer dark ganaches but somehow I love this. It’s not quite as sharply sugary as the usual chocolate fudge buttercream-style icings; it’s sort of a boiled icing but spreadable and thick rather than a thin, poured shell. You can use whatever chocolate icing you like, and experiment with cake toppings.

You will need 2 x 4 inch (10 cm) cake tins. While I haven’t tried it, you might also be able to make these as individual cupcakes.


for the cake batter (2 x 4 inch cakes)
75g plain flour
1/2 tsp cinnamon
1/2 teaspoon baking powder (use up to 1 tsp for a taller, airier cake)
1/4 tsp salt
25g unsalted butter, room temperature
60g smooth peanut butter (1/4 cup)
75g light brown sugar
1 egg (UK medium size, 53g – 63g in the shell)
1 teaspoon vanilla extract
2 tablespoons milk or buttermilk

for the chocolate fudge icing (enough to completely fill and cover this cake)
100g dark chocolate, chopped
5 tbsp (70g) unsalted butter
150g granulated white sugar
150ml double cream
1 tsp vanilla extract
Optional: 1 – 3 tablespoons cold water, or any liqueur of your choice

to finish
flaked sea salt

{optional} further suggestions for cake toppings
sweet and salty popcorn
chocolate-covered peanuts
crushed brittle
finely chopped/grated chocolate
caramelised white chocolate bits



for the cake layer

Preheat oven to 180 degrees Celsius/160 fan.

Grease and line 2 x 4 inch cake tins.

In a small bowl, whisk together the flour, cinnamon, baking powder, and salt.

In another medium bowl, cream together the unsalted butter, peanut butter, and light brown sugar. Beat well for a good few minutes until lighter in colour and texture. Add the egg and vanilla extract, beat until fluffy. Stir in the flour mixture until just combined, then add milk a tablespoon at a time, just to loosen the batter to dropping consistency.

Divide batter evenly between the 2 cake tins, then bake in the oven for 20 – 25 minutes until well risen, springy, and a tester poked into the middle comes out clean. Allow to cool in the tins for about 5 minutes before unmoulding, then let them cool completely.

Only trim and ice the cakes when they’ve reached room temperature. For me, they were cool enough within 1 hour.

for the icing

You can make the icing in advance, or co-ordinate its making while the cakes are baking. Allow at least 1 hour alone for cooling the icing. I let the icing and cakes cool at the same time.

Chop the chocolate into rough little bits. Dice the butter. Set both aside (they’ll be going in together).

Put the cream and sugar into a medium saucepan (mixture shouldn’t come up more than halfway; it’ll bubble up). Bring the mixture to a boil on a medium-high heat, then reduce heat to low and simmer for 3 – 4 minutes. Mixture will bubble and become thick and syrupy.

Remove mixture from heat. Add the chocolate and butter pieces, stirring very well until completely melted and smooth. Add the vanilla extract. Pour the icing into a medium bowl and let it cool completely until smooth and spreadable. You can hasten the cooling by sticking the bowl in the fridge or whisking it over a cold/iced water bath. I stuck it in the fridge for 1 hour, whisking at 20 minute intervals.

If the cooled icing seems broken and greasy, don’t despair. Vigorously beat in cold water or liqueur 1 teaspoon at a time until glossily emulsified.

to assemble & finish

Trim the cakes to make them flat and straight if necessary (I didn’t, obviously, and my cake is super wonky). Split each cake in half, making 4 layers. I score the cake around the outside before shimmying the knife in.

Build your cake on a little plate lined with wide strips of baking paper–the icing clings and makes quite streaky stains. Use around half the icing to fill the cake layers, spreading each layer with at least 2 tablespoons icing. Do a thin crumb coat if you wish, then thickly ice the outside with the remaining mixture, smoothing, swirling, or creating small peaks as you wish.

Sprinkle the top with flaked sea salt and any other delicious things you choose. I wanted sweet and salty popcorn.

Chocolate fudge peanut butter cake

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