Beat in the butter, egg, and coconut sugar in a large bowl until combined.
Add the almond flour, cocoa powder, and salt to the bowl and use a rubber spatula to fold it together and incorporate the dry ingredients until they form a chocolate ball of dough.
Remove the dough and place it in between two pieces of parchment paper. Roll the dough out into a 1/4 inch thick sheet. Slide a baking sheet or cutting board underneath the bottom parchment and chill the rolled dough in the freezer for 10 minutes.
Cut out circular cookies with a cookie cutter (or shot glass). If needed, dip the edges of the cookie cutter or glass into water to prevent it from sticking.
Place the cookies on a baking sheet lined with parchment paper.
Bake for 10-12 minutes.
Allow the cookies to cool for a couple minutes on the baking sheet before transferring to a wire rack to cool completely.
When you’re ready to make the oreos, use a handheld electric mixture to combine the powdered sugar and softened butter. Continue to mix until the butter lightened in color and the filling comes together. Transfer to a plastic ziploc baggie (or piping bag) and cut the corner off.
Pipe the icing out onto half the cookies (feel free to be as generous with the filling as you like – hello quadrupled stuffed!!).
Place the second cookie on top of the filling and give the cookies a little squeeze together.
Store at room temperature for about 3 days or in the fridge for a week.