Make a flax egg by mixing together one tablespoon of ground flax seed with 3 tablespoons of warm water. Let this sit for a few minutes, until the mixture becomes gelatinous.
In a medium bowl, combine the flour, baking powder, baking soda, salt, and spices. Mix these ingredients together well.
In another medium bowl, with an electric mixer, mix together the cashew butter, molasses, brown sugar, vanilla, and flax egg.
Stir the dry ingredients into the wet ingredients. The mixture will be quite sticky, and will seem hard to mix. But keep stirring and the flour mixture will eventually mix in. Divide the cookie dough into two parts, wrap each in plastic wrap, and refrigerate for a couple of hours or overnight.
When you're ready to bake the cookies, roll the dough to about 1/3 inch thickness on a floured surface and cut with cookie cutters. Bake the cookies on cookie sheets lined with parchment paper or a silicone baking sheet for 7 minutes at 350° F.
Allow the cookies to cool on a cooling rack. Decorate as desired.