Preheat the oven to Gas Mark 4, 180°C, fan 170°C.
In a large mixing bowl, cream the butter, sugar, grated and ground gingers together until smooth. Add the flour a little at a time and gradually bring the mixture together until you have a soft dough.
Put the dough on a lightly floured surface and roll or pat out to a circle about 1cm (½ inch) thick.
With a sharp knife or pastry cutter, cut into 8 pieces. Transfer to a nonstick baking street, place a small piece of stem ginger on each one and sprinkle with a little caster sugar.
Bake for 10 minutes or until light golden. Remove from the oven and let cool on a wire rack.
Don't be tempted to use more ginger - either fresh or dried - as it may make your dough too soft.
*Inspired by Mark S. featured in the Realfood Cookbook