1/4cuporganic powdered sugar or ground coconut, for rolling(optional)
Preheat the oven to 350ºF and line a baking sheet with parchment paper. In a large bowl, stir together the ground flax seeds and water.
To the "flax egg", add in the almond butter, coconut sugar, cacao powder, baking soda, vanilla, salt, and vinegar, and stir well until a thick batter is formed. As soon as it looks mixed, stop stirring, so that the batter doesn't get oily.
Use a tablespoon to scoop the dough, then roll the ball between your hands. Dip the ball into powdered sugar or ground coconut, if you want the classic white-crackled look on the outside of your cookies.
Arrange the cookies on the prepared baking sheet at least 2 inches apart from each other. They will spread as they cook. Bake for 10 minutes at 350º, or until the tops of the cookies start to crack.
These cookies need to cool completely on the pan in order to firm up. Store them uncovered at room temperature for up to 3 days, or in an airtight container in the fridge for up to a week.
*If you don't need a vegan cookie, you can most likely swap the ground flax or chia seeds for a real egg. In this case you won't need the 3 tablespoons of water or the added vinegar, either. (The vinegar is simply there to react with the baking soda to help the cookies rise, but eggs will do that anyway.)*To ensure your cookies are vegan, make sure you buy organic powdered sugar. Organic sugar can't be filtered through bone char, like some sugars can be.