Melt half the chocolate and divide evenly between 8 silicone cupcake liners. Spread the chocolate across the bottom of the cupcake liners and slightly up the sides.
Pop the chocolate in the cupcake liners into the freezer for 2 minutes.
Spoon one tablespoon of peanut butter on top of the chocolate and spread across evenly.
Pop the cups back into the freezer for another 2 minutes.
Meanwhile, melt the rest of the chocolate.
Divide the chocolate between the 8 cups and spread on top of the peanut butter. Using a spoon, add a little swirl to the chocolate.