75g (1/2 cup) pistachio kernels, finely chopped, plus extra, finely chopped, to decorate
Preheat oven to 180C/ 160C fan forced. Grease a 24 x 29cm shallow baking pan or Swiss roll pan and line with baking paper, allowing the paper to overhang 2cm above the long sides.
Use electric beaters to beat the eggs and caster sugar in a bowl for 7 minutes or until thick, pale and a ribbon trail forms when the beaters are lifted.
Meanwhile, sift flour, baking powder, ginger and mixed spice 3 times. Fold flour mixture and butter through egg mixture. Spread over prepared pan. Bake for 12 minutes or until centre of the cake springs back slightly when lightly touched. Remove cake from oven. Increase oven to 200C/180C fan forced.
Place a clean tea towel on a work surface with the long edge facing you. Use a fine sieve to dust tea towel evenly with the icing sugar. Working quickly, turn hot cake onto the prepared tea towel and remove baking paper. Use tea towel to roll the cake to form a log. Set aside, seam-side down, to cool completely.