Makes two 20cm round cakes, which can be sandwiched together to make one layer cake.
For the sponge
225g unsalted butter, at room temperature, plus more for greasing tin
225g golden caster sugar
Zest of 1 small orange
4 large eggs, free-range or organic
225g self-raising flour, sifted
For the orange buttercream
125g unsalted butter
15ml freshly squeezed orange juice
150g icing sugar, sifted
Zest of ½ small orange
For the glaze
200g icing sugar, sifted
2 tbsp freshly squeezed orange juice
Preheat the oven to 180 degrees/gas mark 4. Grease two 20centimetre sandwich cake tins and line the base of each tin with baking paper.
To make the sponge, cream the butter, sugar and orange zest in a large bowl with an electric hand mixer. Add the eggs, one at a time, beating well after each addition. If the mixture curdles a little, add some of the flour. Gradually add the remaining flour and beat well, but not for too long.
Divide the mixture evenly between the two tins and smooth the tops with a spatula. Bake in the centre of the oven for 20–25 minutes, until raised and golden brown and a skewer inserted into the centre of one of the cakes comes out clean. Allow the cakes to cool in their tins for 10 minutes before turning out onto wire racks to cool completely.
To make the orange buttercream, beat the butter, orange juice and half the icing sugar together in a bowl. Gradually add the remainder of the icing sugar and then the orange zest and beat until smooth.
To make the glaze, gently pour the orange juice into a bowl containing the icing sugar and beat on a low speed with an electric hand mixer. The glaze should be of a slightly runny, liquid consistency.
To assemble the layer cake, spread the top of one cake with the orange buttercream and place the other on top. Pour the glaze carefully and evenly over the top of the cake, allowing some of it to run over the sides. Decorate with orange zest. Allow the glaze to set a little before serving. Best eaten on the day of baking.
From The Primrose Bakery Bookby Martha Swift and Lisa Thomas, published by Square Peg. Copyright: Martha Swift and Lisa Thomas 2011. Photograph: Yuki Sugiura 2011
