Preheat oven to 350degrees.
Mix flour, cocoa, salt, and baking soda together in a small bowl and set aside.
In a large mixing bowl, beat coconut oil and brown sugar together for about 2 minutes.
Add the egg and vanilla and beat for about 2 more minutes.
Slowly beat in the dry ingredients just until combined.
With a wooden spoon or spatula, stir in the chocolate chips and pistachio's.
Put about 1.5 inch round balls of dough on to a greased cookie sheet. (NOTE-I totally just use two spoons and eye-ball this. You perfectionist can measure and form proper balls, if you like.)
Sprinkle the tops with sea salt and gently press the balls down with greased fingers a bit to give them a flat top.
Bake at 350 degrees for 8-11 minutes or until they look set and the edges look dry.