Ingredients
- 280 grams caster sugar
- 225 grams flour
- 90 grams butter
- 120 grams dark chocolate
- ¾ teaspoon bicarbonate of soda
- 1 tablespoon cocoa powder
- 120 ml buttermilk
- 1 egg
Chocolate Frosting
- 150 grams dark chocolate
- 100 grams butter
- 120 grams icing sugar
- 75 ml buttermilk
Instructions
- Preheat the oven to 160 °C. Grease and line a 15 x 30cm cake tin with baking paper.
- Combine the sugar, chocolate, butter and 180 mL of water in a saucepan and place over a low heat. Stir occasionally until the chocolate has melted and the mixture is smooth. Remove from the heat and allow to cool for 10-15 minutes.
- Add in the sifted flour, sugar and bicarb and whisk until smooth.
- Whisk in the buttermilk and egg and mix until smooth.
- Pour the cake batter into the prepared cake pan. Bake at 180 °C for 45 minutes, or until a skewer inserted into the middle comes out clean. Cool in the pan/
Cake Frosting
- Melt the chocolate in a bowl over a saucepan of simmering water, stirring occasionally, until smooth. Cool the chocolate until it's lukewarm.
- Add the chocolate and butter to a stand mixer and beat until fluffy.
- Beat in the icing sugar and buttermilk and mix until smooth.
- Spread over the cooled cake and serve.
Who says a cake has to be round? This buttermilk slab cake is a great crowd pleaser, not only because of its flavors, but the rectangular shape makes it easy to divide up into many servings. The cake itself is very easy to make, only needing a few steps. The addition of the buttermilk in the recipe helps create an ultra-moist cake crumb and provides a lovely tang to the flavor.
Preparing the Slab Cake
Begin by combining chocolate, sugar, butter and 180mL of water into a large saucepan and place the mixture over a low heat. Stir the mixture occasionally until the chocolate has melted and the mixture is smooth. Remove the mixture from the heat and allow to cool for 10-15 minutes.
Sift flour and bicarb into the chocolate mixture and then whisk everything together until smooth. Add in buttermilk and an egg and whisk until smooth.
Grease a 15 x 30cm cake pan and line it with a sheet of baking paper. Pour the batter into the prepared pan and then bake in a moderate oven for about 45 minutes, until a skewer inserted comes out clean. Let the cake stand in the tin to cool.
Preparing the Frosting
Melt some chocolate in a bowl over a saucepan of simmering water. Stir the chocolate occasionally until it’s smooth. Remove the chocolate from the heat and leave it to cool until it’s lukewarm.
Add the melted chocolate and butter to an electric mixer and beat until the mixture becomes fluffy (this takes about 5-6 minutes). Add in the icing and buttermilk and beat until you have a smooth icing mixture.
Pour the icing over the cake mixture and use a spatula to spread the mixture evenly over the cake. Allow the icing to set before cutting and serving the cake.
Serving the Buttermilk Slab Cake
Try scattering some freeze-dried raspberries crumbled over the top once the cake has been iced. Alternatively, colored sprinkles also add a great pop of colour. Slice into pieces and serve cold.
Notes about the Cake
- Chocolate chips or walnuts can be added to the cake batter just prior to pouring it into the tin for additional flavor.
- The cake keeps nicely for up to a week, and is still just as moist several days after being baked. Store in the fridge.
