Heat oven to 180C/fan 160C/gas 4.

Beat together 225g softened unsalted butter and 225g caster sugar until pale and creamy, then add 4 eggs, one at a time, slowly mixing through.

Sift in 225g self-raising flour, then add the finely grated zest and juice of 1 orange, mix raisin and currents in and mix until well combined.

Line a loaf tin (8 x 21cm) with greaseproof paper, then spoon in the mixture and level the top with a spoon.

Bake for 45-50 mins until a thin skewer inserted into the centre of the cake comes out clean.

While the cake is cooling in its tin, juice 1 orange and add caster sugar to it and mix together. Prick the warm cake all over with a skewer or fork, then pour over the orange sugar.

Leave in the tin until completely cool, then remove and serve. Will keep in an airtight container for 3-4 days, or freeze for up to 1 month.