Chocolate Cream Cheese Filled Cookie Cake

Though this creation is not terribly unique, I'll still classify it as a mad-science experiment because I threw it together in a moment of hungry, chocolate-lusting insanity. I had finished my last slice of birthday cake the day before, so the sudden absence of endorphin-inducing baked goodness resulted in this...

Ingredients:
For the cookie:
1 stick (1/2 cup) butter, softened
1/2 cup shortening, room temperature
1 cup brown sugar
1 tsp baking powder
1/2 tsp baking soda
2 cups flour
1 tsp vanilla
2 eggs
1/2 cup milk chocolate chips, (but I think a full cup would be better)
For the filling:
8 oz cream cheese, room temperature
1/4 cup unsweetened cocoa powder
1/3 cup sugar
1/2 tsp vanilla

Direction:
Preheat oven to 350 degrees. Grease a 9 inch round baking pan.
In a mixing bowl with a beater attachment, combine all the filling ingredient; mix well; set aside.
In a large mixing bowl, combine butter, shortening, sugar; beat until well mixed. Add dry ingredients; then add the eggs; then add the vanilla. Mix well. Lastly, stir in chocolate chips.
In the greased baking pan, press half of the cookie dough into the bottom. Spread the filling evenly over the first cookie dough layer. Top the second layer with the remaining cookie dough.
Bake 35 to 40 minutes.