1 package (14.3 oz) chocolate sandwich cookies (like Oreos)
5 cups mini marshmallows
4 tablespoons unsalted butter
1/2 teaspoon vanilla extract
1/4 teaspoon salt
1/2 cup white chocolate chips (optional for drizzling)
Instructions
Line an 8×8 inch square baking pan with parchment paper, leaving a little overhang on the sides. This will make it much easier to lift the bars out of the pan once they have set. Lightly grease the parchment with a tiny bit of butter or non-stick spray.
Place about 3/4 of the cookies into a large zip-top bag and crush them into medium-sized chunks using a rolling pin. You do not want fine crumbs; having some larger pieces provides a better crunch. Roughly chop the remaining cookies by hand to keep them slightly larger for the topping.
In a large microwave-safe bowl, combine the butter and the mini marshmallows. Microwave in 30-second intervals, stirring in between, until the mixture is completely melted and smooth. Be careful not to overheat, or the marshmallows can become tough.
Stir the vanilla extract and salt into the melted marshmallow mixture. This helps balance the sweetness. Quickly fold in the crushed cookies until they are evenly coated by the marshmallow “glue.” Work fast, as the mixture starts to set as it cools.
Transfer the mixture into your prepared baking pan. Using a buttered spatula or a piece of wax paper, press the mixture down firmly and evenly into the corners. Press the remaining hand-chopped cookie pieces into the top for a beautiful finish.
Let the bars sit at room temperature for at least 1 hour, or place them in the refrigerator for 30 minutes if you are in a rush. Once firm, lift them out using the parchment paper and cut them into 16 squares using a sharp knife.