for the sponge:
butter, for greasing
4 medium eggs
the weight of the eggs in softened butter
the weight of the eggs in caster sugar
the weight of the eggs in plain flour
2 teaspoons baking powder
Preheat your oven to 180°C/Gas 4. Line the base of two 20cm cake tins with parchment paper and lightly butter the sides.
Cream the butter and sugar together until light and fluffy. Add the eggs one at a time, beating well.
Add the flour and baking powder and fold into the mixture until fully incorporated. Divide the mixture between the prepared cake tins.
Bake in the centre of the oven for 20 to 25 minutes. The sponge is ready when the top is golden and has slightly shrunk from the sides of the tin. Leave to cool in the tins for a few minutes before moving to a wire rack to cool.
Choose the best looking sponge as your top layer, then lay the other one – top side down – on your serving plate. Spread the jam over the bottom layer, and then whip the cream to soft peaks and spread over the jam. Place the other layer on top and dust with icing or caster sugar.