Preheat oven to 350 degrees. Spray and flour 9x13 pan.
In large bowl mix together the cake mix according to its instructions and put aside.
In another bowl, using a hand mixer, beat together ricotta cheese, eggs, sugar and vanilla until smooth.
Pour cake batter in 9x13 pan spreading batter evenly.
Carefully pour the cheese mixture evenly over the top of the cake batter.
Spread to cover the cake batter as best you can.

Bake at 350 degrees for 1 hour, remove from oven and let cool completely.
Once the cake is completely cooled, stir the pudding mix and milk together with a whisk until combined.

Carefully fold in the Cool Whip into the pudding until combined.
Spread the pudding mixture over the top of the cooled cake.
Cover cake and refrigerate at least 6 hours.

 

NOTE:

Amazingly, the layers reverse and the cheese sinks to the bottom when cooking.

I refrigerate overnight as I think it tastes better the next day.