preheat oven to 350°F.

mix brownie batter @ directed on box.

line 12 muffin tins w/ liners.

cut cookie dough into 12 1/4 in. slices,and place in bottom of each muffin tin.

spoon batter over the cookie dough,filling about 2/3 full. bake for 20 MIN or until brownies are set.

remove and cool.

when completely cooled,frost your brownies.

FROSTING:

In a large bowl,beat butter,vanilla,and milk( med-low)until smooth and mixed. add powdered sugar and cocoa powder,and beat on low speed until mixed. add chocolate syrup and beat on high,for 2 MIN until light and fluffy.

using a spatula fold in marshmallow cream,just until swirled throughout.