Heat oven to 180C/fan 160C/gas 4. Butter and line the bottom of a deep, round 20cm cake tin with greaseproof paper. Beat the first seven ingredients together in a large bowl (electric hand- beaters are best for this), until pale and thick. Using a large metal spoon, gently fold in the fruit until evenly combined.
Spoon the batter into the tin and bake for 50 mins-1 hr or until the cake is dark golden, springy to the touch and has shrunk away from the tin slightly. A skewer inserted into the centre will come out clean when it’s ready. Cool completely before decorating. Will keep, wrapped in an airtight container or iced, for up to a week, or can be frozen un-iced for up to a month - defrost fully before decorating.