110g (4oz) caster sugar, plus extra for dusting
110g (4oz) butter, softened at room temperature
1 egg, separated
good hefty pinch of ground mixed spice
225g (8oz) plain flour, sieved
50g (1.5oz) currants or seedless raisins
15g (.5oz) candied orange and lemon peel
2 tablespoons of milk
Heat oven to 160C (325F, gas 3). Line baking trays with greaseproof paper.
Cream the butter and sugar together, with a wooden spoon or electric mixer, in a medium to large sized bowl until pale and fluffy. Beat in the egg yolk until well combined.
Fold the flour and spice into the mixture and stir in the fruit and peel.
Add a small amount of milk and bring the mixture together with your hands, adding extra milk if necessary until you have a stiff dough.
Roll the dough onto a lightly floured surface and cut out the biscuits with fluted cutter (6.5cm 2.¾in) to about 3 or 4mm. Place them onto the baking sheets and bake for 10 minutes.
Remove the biscuits from the oven and brush them with the reserved egg white and sprinkle with sugar. Return to the oven for around 10 minutes or until a pale, golden brown colour.
Put the biscuits on a wire rack to cool.