Preheat the oven to 180°C. Lightly butter a 20cm square cake tin and line with nonstick baking paper.
Place the softened butter and sugar into a large bowl and beat with an electric whisk until light and fluffy. Gradually beat in the eggs, one at a time, beating well between each addition. Then beat in the Irish cream.
Sift together the flour, baking powder and salt and then carefully fold into the butter mix using a large metal spoon. Fold in the chopped dried fruit and then spoon the mixture into the prepared tin, smooth the surface and bake for 50 minutes or until golden brown on top and a skewer comes out clean when inserted into the middle of the cake.
Remove from the oven and leave to cool for 10 minutes in the tin. Then remove from the tin, discard the baking paper and place on a wire rack to cool. Dust with icing sugar and serve in thick slices.