There is perhaps no greater duo in the dessert world than dark chocolate and creamy peanut butter. This cake is designed for those who want a high-contrast experience: a deep, moist, almost-black cocoa sponge layered with a salty-sweet peanut butter frosting that tastes like the inside of a premium truffle. It is decadent, tall, and guaranteed to be the most talked-about dish at any gathering.

Time:

1 hour, with 15min for cooling

Serves:

10-12

Good for:

• Birthday or any celebration   
• A showstopper dessert
• Kid approved – make sure they have no allergies

Ingredients:

For the Chocolate Sponge:

• 250g All-purpose flour
• 400g Caster sugar
• 75g High-quality cocoa powder (unsweetened)
• 10g Baking powder
• 5g Bicarbonate of soda
• 5g Sea salt
• 250ml Whole milk (at room temperature)
• 120ml Vegetable oil
• 2 Large eggs
• 5ml Vanilla extract
• 240ml Boiling water (to “bloom” the cocoa)

For the Peanut Butter Frosting:

• 250g Creamy peanut butter (avoid the “natural” oil-separating kind for better structure)
• 200g Unsalted butter, softened
• 400g Icing sugar, sifted
• 45ml Heavy cream
• 5ml Vanilla extract

Kitchen things you’ll need:

• 2 20cm round cake tins
• Electric hand mixer or stand mixer
• 2 large mixing bowls
• Sieve (for dry ingredients)
• Offset spatula (for smooth frosting) – or use a butter knife
• Wire cooling rack

Making it:

• Preheat your oven to 180°C. Grease and line your cake tins with baking paper. Sift the flour, sugar, cocoa, baking powder, bicarb, and salt into a large bowl. Whisk to combine. Add the eggs, milk, oil, and vanilla. Beat on medium speed for about 2 minutes.
• Turn the mixer to low and slowly pour in the boiling water. The batter will be very thin—this is normal! Stir by hand until smooth. Divide the batter equally between the two tins.
• Bake for 30–35 minutes. Test with a skewer; it should come out clean. Let the cakes cool in the tins for 10 minutes, then transfer to a wire rack to cool completely.
• In a clean bowl, beat the softened butter and peanut butter together until pale and fluffy (about 3 minutes). Gradually add icing sugar, one cup at a time. Add the cream and vanilla, then whip on high for another 2 minutes until it looks like a cloud.
• Level the tops of your cakes with a knife if they have domed. Place one layer down, spread a thick layer of frosting, top with the second cake, and cover the top and sides with the remaining frosting.

Tips/notes:

• Add 50g of crushed roasted peanuts into the frosting for a “crunchy” version.
• Pour a simple chocolate ganache (equal parts hot cream and chocolate) over the top edges for a professional “drip” look.
• If your frosting is too stiff, add an extra tablespoon of cream. If it’s too soft, chill it in the fridge for 15 minutes before frosting the cake.