In a medium saucepan over medium heat, melt butter, then stir in light brown sugar, salt, vanilla extract, and bourbon. Cook until thick and amber.

Pour toffee onto a parchment-lined baking sheet and let cool, then chop into pieces.

Preheat oven to 275°F. In a large bowl, combine cornflake cereal, milk powder, white sugar, and salt. Drizzle with melted butter and mix.

Spread cornflake mixture on a baking sheet and bake for 20 minutes until crispy. Let cool.

Brown butter in a saucepan and mix with light brown sugar and white sugar until fluffy. Add eggs and vanilla extract.

In a separate bowl, whisk flours, baking soda, and baking powder, then gradually mix with wet ingredients.

Fold in cooled cornflake crunch and chopped toffee into the dough. Cover and refrigerate for at least 8 hours.

Preheat oven to 350°F. Scoop and roll cookie dough into balls on a parchment-lined baking sheet.

Bake for 9-10 minutes until edges are golden and centers appear underbaked. Set to cool.

Sprinkle warm cookies with chopped toffee pieces and edible gold glitter.