01 - Line an 8x8-inch baking dish with parchment paper, ensuring the paper extends over the edges for easy removal.
02 - In a medium saucepan over low heat, combine the peanut butter and maple syrup. Stir constantly until melted and smooth, about 2 to 3 minutes.
03 - Remove the saucepan from heat and gently fold in the crushed corn flakes until every piece is evenly coated with the peanut butter mixture.
04 - Transfer the mixture into the prepared baking dish and press firmly into an even, compact layer. Place in the freezer for 20 to 30 minutes until set and firm.
05 - Combine the dark chocolate chips and coconut oil in a heatproof bowl set over a pan of simmering water. Stir gently until completely melted and smooth.
06 - Remove the peanut butter slab from the freezer and lift it out of the dish using the parchment overhang. Cut into 12 even bars using a sharp knife.
07 - Using a fork or dipping tool, submerge each bar into the melted chocolate, coating all sides. Tap gently to remove excess chocolate and place on a parchment-lined tray.
08 - Refrigerate the coated bars for at least 20 minutes, or until the chocolate shell is fully hardened and set.