For the sponge
4 eggs, large, free-range
225g caster sugar, plus extra for sprinkling
225g self-raising flour
1 tsp baking powder (+1Tbl to recreate self-rising)
(¾ tsp salt to recreate self-rising)
225g unsalted butter, softened, plus extra for greasing
For the jam
250g jam sugar
For the buttercream
100g unsalted butter, softened
200g icing sugar, sifted
2 Tbl milk
Preheat the oven to 180°C (356F). Grease and line 2 x 20cm(8”) sandwich tins(cake pans): use a piece of baking or silicone paper to rub a little baking spread or butter around the inside of the tins until the sides and base are lightly coated. Line the bottom of the tins with a circle of baking paper.
Break the eggs into a large mixing bowl, then add the sugar, flour, baking powder and soft butter.
Mix everything together until well combined. Be careful not to over-mix – as soon as everything is blended you should stop. The finished mixture should be of a soft ‘dropping’ consistency.
Divide the mixture evenly between the tins. Use a spatula to remove all of the mixture from the bowl and gently smooth the surface of the cakes.
Place the tins on the middle shelf of the oven and bake for 25 minutes. Don’t be tempted to open the door while they’re cooking, but after 20 minutes do look through the door to check them.
While the cakes are cooking, make the jam. Place the raspberries in a small deep-sided saucepan and crush them with a masher. Add the sugar and bring to the boil over a low heat until the sugar has melted. Increase the heat and boil for 4 minutes. Remove from the heat and carefully pour into a shallow container. Leave to cool and chill to set.
The cakes are done when they’re golden-brown and coming away from the edge of the tins. Press them gently to check – they should be springy to the touch. Remove them from the oven and set aside to cool in their tins for five minutes. Then run a palette or rounded butter knife around the inside edge of the tin and carefully turn the cakes out onto a cooling rack.
To take your cakes out of the tins without leaving a wire rack mark on the top, put the clean tea towel over the tin, put your hand onto the tea towel and turn the tin upside-down. The cake should come out onto your hand and the tea towel – then you can turn it from your hand onto the wire rack. Set aside to cool completely.
For the buttercream, beat the butter in a large bowl until soft. Add half of the icing sugar and beat until smooth. Add the remaining icing sugar and one tablespoon of the milk and beat the mixture until creamy and smooth. Add the remaining tablespoon of milk if the buttercream is too thick. Spoon the buttercream into a piping bag fitted with a plain nozzle.
To assemble, choose the sponge with the best top, then put the other cake top-down onto a serving plate. Spread with the jam then pipe the buttercream on top of the jam. Place the other sponge on top (top-side up) and sprinkle with caster sugar to serve.