6 oz Hershey Cookies and Cream bar, roughly chopped
2 sticks unsalted butter, slightly softened
1/2 cup half and half
3 tsp vanilla extract
4 cups powdered sugar
10 Oreo cookies, finely crushed
Make the brownie mix as per directions on the box. Once it is made up, add in the 12 Oreo cookies and the Hershey bar. Stir together, dump into a baking try and bake according to directions.
For the frosting, cream together the butter, half and half, vanilla and about half of the powdered sugar. Continue adding the sugar a bit at a time until you have reached a creamy and slightly less than stiff mixture.
Add in the 10 crushed Oreos and stir until combined.
Once the brownies are finished, remove from oven and cool completely.
Frost with the frosting mix and then place in the fridge for at least an hour until firmly set.