In a large bowl, beat the butter, brown sugar and maple syrup with an electric mixer until pale and fluffy. Beat in the egg and ginger.
In a small bowl, stir together the flour, cinnamon, allspice, baking soda and salt; add to the butter mixture and beat on low speed or stir by hand until you have a soft dough. Divide the dough into 3 pieces, wrap each in plastic and refrigerate for 2-3 hours, or up to a day.
When ready to bake, preheat the oven to 350F. On a well-floured surface, roll the dough out 1/4-inch thick. Cut into shapes and bake on a parchment-lined sheet for 10 minutes, or until pale golden. Cool completely before decorating.