- For the sheet cake:
- 170 g unsalted butter, at room temperature, for greasing
- 320 g flour
- 3 t baking powder
- 1/2 t fine sea salt
- 350 g caster sugar
- 3 large eggs
- 2 t vanilla extract
- 175 ml sour cream
- For the chocolate fudge frosting:
- 340 g unsalted butter, at room temperature
- 120 g icing sugar
- 2 T golden syrup or clear honey
- 60 g cocoa powder
- 80 ml hot water
- 80 ml sour cream
- 1 t vanilla extract
- 200 g dark chocolate (70% cocoa solids), melted and cooled
- To decorate:
- Sprinkles of your choice
1. Preheat the oven to 180°C. Lightly grease a 23cm x 33cm x 5cm baking tin and line the base with a piece of parchment paper.
2. For the cake, place the flour, baking powder and salt into a large bowl and whisk briefly to combine. Add the butter and sugar to a separate large bowl and, using an electric mixer, beat together on medium-high speed for about 5 minutes until light and fluffy.
3. Add the eggs, one at a time, beating until fully combined before adding another. Add the vanilla and mix briefly to combine.
4. Add the flour mixture in three additions, alternating with the sour cream, starting and finishing with the flour. Scrape the batter into the prepared tin and level out.
5. Bake for 35–40 minutes or until the cake springs back to a light touch. Leave to cool in the tin.
6. For the fudge frosting, place the butter in a large bowl and use an electric mixer to beat on high speed for a couple of minutes or until creamy and smooth.
7. Add the sugar, golden syrup (or honey) and cocoa powder and beat on high speed for 5 minutes or until light and fluffy. Add the hot water, sour cream and vanilla to a small jug and whisk together.
8. Add the sour cream mixture to the bowl and mix on medium speed until combined. It will look separated for a while but will come back together as a smooth frosting.
9 . Add the melted chocolate and beat briefly until smooth and silky. Spread the frosting over the cake, finishing with a generous amount of sprinkles, which as far as I am concerned are mandatory.
10. Cut into squares to serve. Store in a sealed container for up to 3 days.
Cook's note: It’s the law, birthday cake needs to include both chocolate and sprinkles, lots of sprinkles. When I was little, the birthday cake of choice was a simple cocoa affair topped with melted milk chocolate and decorations made from Smarties, chocolate fingers and any other candy desired that year. This recipe feels like another of those classic cakes, a simple yellow cake base and a chocolate fudge frosting. As this is not a layer cake, the fudge frosting doesn’t need to be thick enough to hold a second cake layer. It’s silky and smooth and stays that way, it won’t harden over time.
This is an extract from One Tin Bakes by Edd Kimber. It is published by Kyle Books and retails for R329. Photography: Edd Kimber