Preheat the oven to 350 F and very generously grease a 10x15" baking sheet with oil.
Using a large bowl, whisk the ground flax and water together. Allow to set and thicken for 5 minutes.
Add the remainder of the ingredients (reserving the salt) to the bowl and mix well to fully combine.
Place the cookie dough onto the greased baking sheet and use a rubber spatula (or your hands) to evenly flatten the dough cover the entire baking sheet.
Transfer to the oven and bake for 10-12 minutes or until the cookie is fully baked through.
Remove from the oven and top with sea salt. Allow to cool slightly before carefully using a spatula to slice pieces of the cookie. Serve with a fork and enjoy!
Notes
All nutritional information are estimations and will vary. Estimations do not include optional ingredients.