In a food processor, grind up about 10-12 of the cookies to a fine powder. Once fine, pour in powdered sugar and pulse or stir to combine. Set aside.
18-20 Biscoff or speculoos cookies, 1½ cup powdered sugar
Create a double boiler by placing a small saucepan, about ⅓ of the way full of water, over the stove at medium heat. Add a heat-safe bowl on top, making sure it is wide enough to not sink into the pot or touch the water. Bring the water to a simmer
To the bowl over the water, add in the white chocolate chips, butter, and cookie butter. Let the steam from the water underneath gently melt the ingredients, whisking or folding with a rubber spatula to combine.
½ cup unsalted butter, 1⅓ cup white chocolate chips, ⅔ cup cookie butter
Once smooth, remove the bowl from the heat and stir in the vanilla.
1 tsp vanilla extract
To a larger bowl (with a lid), add in your Chex mix. Pour the melted chocolate, cookie butter mixture over top, and use a rubber spatula to gently fold everything until evenly combined.
1 12oz box Chex rice cereal
Once combined, pour over the cookie-powdered sugar mix. Cover with an airtight lid and shake vigorously to coat each piece with the powdered sugar.
Once each piece is coated, take the remaining cookies and break them up by hand into small pieces. Add these to the Chex mixture and gently fold into the mix.
18-20 Biscoff or speculoos cookies
Serve warm or store in an airtight container for up to one week.