Heat the oven to 350°F, and line a baking sheet with a piece of parchment paper.

Add the peanut butter, flour, brown sugar, baking powder, egg, salt, and vanilla in a medium bowl and mix until well combined. Divide the dough into 14 equal rounds (33g each). Place the rounds on the prepared baking sheet and slightly flatten each one until about 2 ¼-inch wide in diameter. Then, using the tines of a fork, press down on each round in perpendicular directions to create a crisscross pattern.

Bake the cookies for 10-11 minutes, or until the edges are set. Let the cookies cool on the pan for 5 minutes, and then transfer to a cooling rack to cool completely. Once the cookies are room temperature, gently wrap them in plastic and place in the freezer to chill completely, about 2 hours. This will make them a bit more durable since these cookies are so soft.

To prepare the sandwiches, remove the pints of ice cream from the freezer and use a serrated knife to cut ¾-1-inch thick slices by cutting through the paper container. Moving quickly, use a 2½-inch wide biscuit cutter to cut out uniform rounds of ice cream to sandwich between the cookies. You will end up with 7 sandwiches altogether.

To make the chocolate hard shell, simply melt the chocolate chips and coconut oil together in a microwave safe bowl and whisk until smooth. Decorate the cookies as desired, either by dipping in or drizzling with the chocolate hard shell, then garnish with crushed peanuts if desired. Place the sandwiches back in the freezer for 10-15 minutes to firm up before enjoying.