In a small bowl or measuring cup, slowly whisk the water and flax meal with a fork. Set aside to thicken. Preheat the oven, line two large rimmed baking sheets with parchment paper.
Bake one sheet at a time on the middle rack until the cookies are lightly golden brown on the bottoms. Remove from the oven and let the cookies cool on the baking sheet before transferring to wire racks to cool completely.