Chocolate Gooey Butter Cake

Who doesn't love gooey butter cake?  And what could possibly make it better . . . why, chocolate, of course.

1 (18.25 oz) package chocolate cake mix
3 large eggs
1 cup (2 sticks) butter
1 (8 oz) package cream cheese (at room temperature)
3 Tbsp unsweetened cocoa powder
2 cups powdered sugar
1 tsp vanilla extract

Preheat oven to 350 degrees.  Spray a 9 x 13" cake pan with non-stick cooking spray.

In a large bowl, combine the cake mix, 1 egg and 1/2 cup of melted butter.  Stir until well blended.  Pat the mixture into the pan and set it aside.

Beat the cream cheese until smooth.  Add the two eggs and the cocoa powder and beat until well mixed.  Reduce the speed of the mixer to low and add the powdered sugar.  Beat until well mixed.  Slowly add the remaining 1/2 cup melted butter and vanilla.  Beat until smooth.  Spread over the top of the batter in the pan.

Bake the cake for 40 minutes.  The center should be slightly gooey.  Slice and serve with whipped topping, if desired.  I actually like to sprinkle a little bit of powdered sugar over the top.