for the sponge • large free-range eggs • g/8oz caster sugar, plus extra for sprinkling • level tsp baking powder • g/8oz unsalted butter, softened, plus extra for greasing • For the jam • g/7oz raspberries • g/9oz jam sugar • For the cream • g/3½oz unsalted butter, softened • milk • g/7oz icing sugar, sifted