Preheat oven to 300 degrees F (150 degrees C). Grease a 9-inch pie dish.
Blend coconut milk, walnuts, eggs, coconut flour, cocoa powder, maple syrup, butter, vanilla extract, and salt in a blender until smooth; pour into the prepared baking dish.
Bake in the preheated oven until set but still soft, about 1 hour. Cool pie to room temperature, about 30 minutes. Lightly cover pie with plastic wrap and refrigerate until chilled, 8 hours to overnight.
