1. Gather all ingredients: semi-sweet chocolate, unsalted butter, cornflakes, and any optional additions like almonds or peanut butter.
2. Break the chocolate into smaller pieces for easier melting.
3. In a heatproof bowl, combine chocolate and butter.
4. Melt the chocolate and butter using a double boiler or microwave in 20-second intervals, stirring until smooth.
5. Once melted, mix well to ensure a smooth and even consistency.
6. Add cornflakes to the melted chocolate mixture.
7. Gently stir until all cornflakes are fully coated with chocolate.
8. If adding optional ingredients like nuts or peanut butter, mix them in now.
9. Line a baking sheet with parchment paper.
10. Using a spoon, scoop portions of the mixture and drop them onto the lined baking sheet.
11. Shape each portion into small mounds or press into a pan if making bars.
12. Place the baking sheet in the refrigerator or freezer to chill.
13. Let the cookies set for at least 30 minutes or until firm.
14. Once set, remove from the fridge and serve.
15. Store leftover cookies in an airtight container at room temperature or in the refrigerator.
16. Enjoy your crunchy and chocolatey cornflake cookies!