220g butter, softened, plus extra for greasing
220g caster sugar, plus extra for dredging
4 large eggs, lightly beaten
220g self-raising flour - to make this recipe gluten-free I used Doves Self-Raising Flour
Zest and juice of one large orange
Up to six tablespoons of freshly squeezed orange juice
Preheat your oven to 180°C, gas mark 4 (the temperature at which most cakes are baked). Line the bottom with greaseproof paper and grease the sides of two 20cm-diameter sponge tins.
A sponge is made by the creaming method; that is, the fat and sugar are creamed or beaten together until light and fluffy before other ingredients are added. It's important to beat the butter and sugar well, as this incorporates lots of air which makes the cake light. Begin with very soft butter, add the sugar and beat with an electric whisk for 2 minutes, until fluffy and pale. I find 5 minutes works even better.
Now add the eggs. Beat them lightly first to break them up. Add a quarter of the egg, plus a spoonful of flour and beat on the lowest speed until completely incorporated. Adding the egg gradually along with a little flour should stop the mixture curdling, or forming tiny lumps, which can make the cake heavy. Add the remaining egg in the same way.
Add the remaining flour and fold in with a large metal spoon. Self-raising flour is used because it contains raising agents to give the sponge extra lift. Add a fresh orange juice, one tablespoon at a time, if necessary to achieve dropping consistency - this means a scoop of the mixture will slowly fall off a spoon when held sideways, rather than running off easily, or sticking completely.
Divide the mixture between the two greased cake tins, smoothing the tops. Put in the oven - preferably on the same shelf - and bake for 20 minutes. The cakes should look well-risen and golden brown, and should have pulled away slightly from the sides of their tins. To make sure the cakes are done, push a metal or wooden skewer into the middle of one. It should come out clean, or with only a few dry crumbs attached. If there's sticky-looking cake mix on it, bake for 5 minutes more, then repeat the test.
After 10 minutes cooling in the tin, turn the cakes out on to a wire rack (if you turn them out when hot, they may break up). Put the smoothest-looking cake right side up (this will be the top of the finished cake) and the other upside down, so its domed top flattens slightly. Leave to cool completely.
Orange Buttercream Icing:
300g of sifted icing sugar
150g of unsalted butter - make sure it's very soft
Zest of half an orange
Half a teaspoon of vanilla essence
Sift the icing sugar into a bowl. This ensures the icing is very light and doesn't clump together
Put the soft butter into a bowl and add a little icing sugar - start to mix with an electric beater on slow - otherwise you'll be enveloped in a cloud of sugar
Add a few more tablespoons of the icing sugar and combine
Add the rest of the icing sugar in manageable batches
Once blended add the orange zest and beat some more
Add vanilla essence and beat some more
The longer you beat the lighter the icing will turn out. So beat away..........