Line a 8x8-inch square baking pan with parchment paper or lightly grease it; set aside.
Place the chocolate chips, creamy peanut butter, honey, and unsalted butter in a large microwave-safe mixing bowl.
Microwave the mixture on high for 2 minutes, then remove and stir until the chocolate is fully melted and the mixture is smooth and combined.
Gently fold the cornflakes into the chocolate-peanut butter mixture until evenly coated, taking care not to crush the cereal.
Transfer the mixture to the prepared pan, press and smooth it evenly into the pan with a spatula.
Refrigerate until firm, about 2–4 hours, then slice into bars with a sharp knife.
Store the sliced bars chilled.