In a saucepan, melt the chocolate and unsalted butter over low heat. Stir continuously to ensure the mixture doesn't burn or stick to the bottom.
Gently fold in the cornflakes with the melted chocolate and butter, ensuring that they are evenly coated.
Using a spoon, place small mounds of the chocolate-coated cornflakes onto a baking tray lined with parchment paper. You can shape them into neat clusters or leave them in a more rustic, freeform style. You can also use a muffin tray if you wish, or disposable muffin cups.
Place the baking tray in the refrigerator to allow the chocolate cornflakes to set for at least 1 hour. Once firm, your delectable chocolate cornflakes are ready.