Preheat the oven to 360C/ gas mark 4. Line an 8 inch square tin with aluminum foil. (This will make it easier to lift out the finished biscuits/cookies).
Cream the butter and sugar together in a bowl until light and fluffy.
Sift together the flour, baking powder and ground ginger. Stir this into the creamed mixture, mixing everything well together.
Press into the prepared tin and bake for 15 to 20 minutes. (They should be pale golden brown.)
For the glaze combine the butter, icing sugar, ground ginger and syrup in a small saucepan. Stir over a gentle heat until well mixed together.
Pour over the biscuit (cookie) layer while both are still warm. Cut into squares immediately and let cool completely. Decorate each square with some of the stem ginger if using.
Leave until completely cold to lift out. Store any leftovers in an airtight container.
