Start with the cake. Turn the oven on to 180C. Grease the tins, line the bottom of both tins with grease proof paper and then lightly flour them.
Using a mixer, cream the butter and sugar.
Mix the eggs together in a separate bowl then pour them into your mixer
Sieve in the flour
Add the orange zest
Split the mixture evenly between the two cake tins and then bake in the oven for around 25- 30 minutes until they are golden brown and feel slightly springy on top.
While they are baking make your jam and icing. For the jam put the raspberries, orange juice and heaped tablespoon of golden caster sugar into a small pan. Heat gently and allow to slowly break down and reduce into a jammy consistency, then leave to cool.
For the icing, mix the softened butter with the sieved icing sugar, juice of ½ an orange and the zest of a whole orange
When the cakes are cool – spread some icing on to the top of one sponge, then some jam, then sandwich them together and spread the remaining buttercream over the top. Zest over a little more orange to serve.