Preheat oven to 350 degrees.
Grease a 9x13 baking dish.
In a large bowl beat 1 egg then mix in cake mix and melted butter.
Press the dough into the baking dish, covering the bottom.
In another large bowl add cream cheese, 2 beaten eggs and vanilla.
Slowly blend well with an electric mixer.
Pour on top of the crust in the baking dish.
Bake 40 to 45 minutes.
Remove and let cool for at least 15 minutes before cutting into squares and serving.
Optional: you can dust with powdered sugar on top before serving.