Preheat the oven to 160C/325F/gas mark 3
Use a 900g/2 lb loaf tin.
Grease the loaf tin and line the base with greaseproof paper. Grease the paper. Cream the butter and sugar in a small bowl with an electric mixer until light and fluffy. Transfer the mixture to large bowl. Stir in figs, ginger and walnuts, then sifted flours and the sour cream. Spread the mixture into the prepared tin. Bake for about 1 1/4 hours. Stand 5 minutes before turning on to wire rack to cool.
