Whisk together the ground flax and water, and allow to sit for 1-2 minutes.
Cream the room-temperature butter and brown sugar until light and fluffy, about 2 minutes.
Add the flax egg and molasses to the butter and sugar. Mix until combined.
Add the baking powder, baking soda, nutmeg, ginger, cinnamon, and salt. Fold together to combine.
Add the flour a half a cup at a time.
Cover and refrigerate the dough for 2 hours.
Remove the dough from the refrigerator. Preheat the oven to 375°F. Line a baking sheet with parchment paper.
Roll the dough into 1-inch balls, and then roll the balls in cane sugar and then the powdered sugar.
Place the balls on the prepared baking sheet 2 inches apart.
Bake for 9-10 minutes or until flattened, crackling, and golden brown.
Cool the cookies on the baking sheet for 5 minutes, before transferring to a wire rack to cool completely.