Step 1

Preheat the oven to 350 degrees F. Spray a 9-by-13-inch rimmed baking sheet with cooking spray.

Step 2

Put the cookies in a food processor and pulse until you have crumbs. Transfer the crumbs to a medium bowl and stir in the melted butter. Press the mixture evenly over the bottom of the prepared pan.

Step 3

Pour the sweetened condensed milk over the crust and spread evenly. Top with the coconut flakes, white chocolate chips and the cereal nuggets, pressing the cereal in firmly. Bake for 20 minutes.

Step 4

Remove the pan from the oven and sprinkle the charm marshmallows on top. Press the charms firmly down with a spatula and continue to bake until the bars are golden brown, about 10 minutes longer. Cool in the pan before cutting into 24 bars.