Preheat oven to 350 degrees.
Prepare flax egg by combining 2 TBSP of flaxseed meal with 5 TBSP of warm water and set aside to allow the mixture to thicken.
In a medium bowl, whisk together almond flour, coconut flour, baking soda, and salt. Set aside.
In a separate bowl, cream together the almond butter (or peanut butter if you're using that), melted and cooled coconut oil, coconut sugar, almond milk, and vanilla extract until smooth.
Add wet almond butter mixture to your dry ingredients and fold to combine.
At this point, the flax egg should be thick. Add it to the cookie dough and stir to combine.
Roughly chop up your favorite chocolate bar (I used a 70% bar) into small pieces. Fold 3/4 of the chopped pieces into the batter, and reserve 1/4 of the pieces (so you can press them into the tops of the cookies prior to baking!)
Form dough into 2 inch cookies and place on a lightly greased cookie sheet. Press down slightly to flatten. Once you've formed all of the dough into cookies, gently press the rest of the chopped chocolate bar into the tops of the cookies.
Bake for 18-20 minutes at 350 degrees. Sides and bottoms of cookies should be golden brown.