Preheat the oven to 150°C, fan 130°C, gas 2. Grease a 19cm round cake tin and line the bottom and sides with baking parchment.
Put the butter and sugar in a large mixing bowl. Cream together using a hand-held electric whisk. Gradually whisk in the eggs, then fold in the flour and the mixed fruit. Spoon the mixture into the tin and smooth the top.
Bake for about 3 hours 45 minutes to 4 hours (cover with greaseproof paper if it’s getting too brown) or until a skewer inserted into the middle of the cake comes out clean.
Cool in the tin for 15 minutes. Turn out on to a wire rack to cool. Decorate when cold.