Combine peanut butter, coconut flour and maple syrup in bowl. Firmly pack into an 8x8 baking dish to form an even layer about 1/2" thick.
Freeze the base while you prepare the topping.
Add dark chocolate, peanut butter and coconut oil to a bowl. Heat bowl gently in the microwave or over a saucepan filled with simmering water on the stove until chocolate has fully melted.
Remove base from freezer and pour dark chocolate mixture over crust. Sprinkle with walnuts, puffed amaranth, sea salt flakes or other add-ins you desire! (Dried fruit, pistachios, almonds?)