Chop the chocolate and melt it in the microwave for 45 seconds to 1 minute, stirring halfway through to help it melt evenly.
Pour about two-thirds of the melted chocolate into your Halloween mould and place it in the freezer for 2–5 minutes, just until it firms up.
Meanwhile, mix the peanut butter, powdered peanut butter, and maple syrup in a small bowl. I like to add a pinch of salt here too—it really brings out the flavour—but that’s optional. Stir until a thick, compact dough forms.
Spoon about ½ teaspoon of the peanut butter mixture into each mould, pressing it down gently with your fingers so it fits neatly into the shape. It should be just enough to fill all the moulds (mine made x pieces).
Finally, pour the remaining melted chocolate over the top to seal in the filling, then pop the moulds back into the freezer for about 5 minutes until fully set.
Once firm, just pop them out and enjoy your homemade Halloween peanut butter chocolates!