In a medium bowl, whisk flour, cream of tartar, baking soda, salt, ginger, cinnamon, nutmeg and allspice together. Set aside.
In a large bowl, beat butter and sugar until creamy.
Pour molasses, water and egg into bowl and beat until combined.
Gradually add flour mixture into sugar mixture and mix until combined.
Divide dough in half and form two balls. Set each ball of dough on plastic wrap and press down into a disk, wrap in plastic wrap and place in fridge for about an hour.
Preheat oven to 350° and lightly spray two baking sheets with non stick spray.
Remove dough from fridge, and on a lightly floured surfaced roll dough to approximately ⅛ inch thick.
Cut dough with a gingerbread cookie cutter.
Place on prepared baking sheets 2" apart, bake for 9-10 minutes or until edges start to firm up.
Remove from oven and transfer to wire rack to cool completely.
Decorate as desired.