Make the peanut butter cookie dough. In a large bowl combine peanut butter, maple syrup, vanilla extract, kosher salt, and coconut flour. Stir using a sturdy spoon or spatula, until well mixed and no bits of dry coconut flour remain.
Allow the dough to thicken. Set aside for about 5 minutes so the coconut flour can absorb any moisture in the dough. If after 5 minutes the dough seems too sticky to handle, add a little more coconut flour at a time – I would start with just 1 teaspoon and go from there.
Form into cookie shape. Once the dough is the consistency of a thick cookie dough, roll it into 1 inch size balls. Gently press to shape and flatten, pinching the edges together if they start to crack. Make criss cross marks with the tongs of a fork if desired.
Chill the cookies to set. Chill in the refrigerator for at least 30 minutes, or in the freezer for 10-15. While the cookies are chilling, go ahead and melt your dark chocolate if using.
Dip in chocolate. Carefully dip each cookie about halfway into the melted chocolate and move to a parchment lined plate or cutting board. You can also add a little drizzle of chocolate on top to make them extra pretty.
Top with a sprinkle of flaky sea salt if desired and return to the refrigerator or freezer so the chocolate can harden.
Serve and enjoy!