Preheat the oven to 375F / 190C and line a baking sheet with parchment paper.
In a small bowl, add the milled flaxseed to the water and stir well to make your flax 'egg'. Set aside for 10 minutes, stirring a couple of times to help it thicken.
Add the oats, oat flour, ground ginger and salt to a bowl. Spoon in the pumpkin seed butter, maple syrup and flax egg.
Stir really well, so the wet ingredients combine with the dry ingredients. Use a wooden spoon to 'mash' the pumpkin seed butter if it's a bit thicker so it breaks up and combines with the oats and syrup.
Using your (wet) hands or a cookie scoop, scoop out about two heaped tablespoons of the cookie mixture, and form a cookie. Place on the baking sheet, and repeat for the remaining mixture.
Bake the cookies for 10-12 minutes until they are slightly browned on the edges. Remove from the oven and carefully place on a wire rack. They will still be quite soft at this point. Leave for a few minutes to cool down, then enjoy!