This was inspired by the fact that I had left over chocolate chip cookie dough and it wasn't going to make enough cookies for the group I was making a dessert for, so I quickly looked up for a recipe on Allrecipes.com and up pops THE perfect solution. I used my own chocolate chip cookie recipe that is on my blog and it is a little different than the one on the recipe page mentioned earlier. So I would use half of that recipe for the cookie base and then the following to make the Brookie.
Use half of this recipe http://step-by-stepcooking.blogspot.com/2012/10/chocolate-chip-cookies.html for the cookie base. Spread it in the bottom of a 9 x 13 pan make it no more than 1/2 inch think.
Then for the brownie part:
1 cup of sugar
1/2 cup of butter that has been melted
1 tsp vanilla
1/2 cup flour
1/4 tsp baking powder
1/8 tsp salt
Add to the egg, butter, sugar mixture.
Stir to combine all ingredients.
Pour the brownie batter over the cookie dough in the pan.
Bake at 350 degrees (175 C), for 20-25 minutes. Use a toothpick poked in the center to check it, if the toothpick comes out clean, it is ready.