For the cupcakes

1. Preheat your oven to 350 F (175 C) and place your favorite cupcake papers in your cupcake pans. Add a whole cookie to the bottom of each cup.
2. In a large mixing bowl, beat together cake mix, butter, water, and eggs with an electric mixer on low for about a minute. Turn up the speed to medium high for another minute to make sure everything is smooth.
3. Scoop your batter evenly into your cups, filling them about two thirds full. Bake for 20 minutes or until a toothpick comes out clean.
4. Let the cupcakes cool in the pan for about five minutes then remove them to a rack. Allow the cupcakes to cool completely.

For the filling

1. In a mixing bowl, beat together marshmallow cream, butter, vanilla and heavy cream until smooth. Slowly mix in the powdered sugar, then beat on medium high for about a minute until everything is smooth. Transfer mixture to a piping bag with a small round tip.
2. Use a chopstick or something similar to poke a hole in the center of each cupcake. Poke the piping tip down into the hole of each cupcake and squeeze in some of your filling.

For the frosting

1. In a large mixing bowl, beat together butter, heavy cream, and vanilla until smooth. Turn mixer down to low and slowly add in the powdered sugar. Crank up the speed for a minute or two to make everything smooth and fluffy.
2. Fold in your cookie crumbs, and frost your cupcakes in your favorite way.