Double cream and strawberry jam (optional filling)
Preheat the oven to 180C/electric. Grease two 20 cm cake tins and line with parchment paper.
In a large bowl whisk the butter and sugar together until combined. Then, add the eggs one at a time and mix. Then, add all the single cream and mix once again.
With a wooden spoon fold in the flour a third at a time until the mixture is smooth.
In a separate bowl place the mashed strawberries and vanilla extract and mix gently with a small metal spoon. Add the strawberry mixture to the smooth cake mixture and combine.
Pour the mixture into the cake tins and bake on a middle shelf for 20 minutes.
Take out of the oven and leave to cool in the tins for 30 minutes before removing. After cooled, spread as much jam as desired on one of the two sponges. Then whip some double cream and place on top of the jam. Take the other sponge and sandwich both sponges together. Serve!