In a large bowl, mix together the cake mix, one egg and the oil until a crumbly consistency. Set aside 1 cup of the crumb mixture for later.
Grease a 9×13 inch baking pan and pat the crumb mixture into the pan. Bake in a preheated 350°F oven for 10 minutes. Set aside.
Add the cream cheese to a large bowl. Beat with a mixer on medium speed until smooth. Add sugar, vanilla and egg to a bowl and beat until smooth. Spread cream cheese mixture evenly over crust in baking pan.
Sprinkle the 1 cup of crumb mixture on top of the cream cheese.
Bake for 15 to 18 minutes or until topping is golden. Remove from heat and let cool.
Before cutting into bars, sprinkle powdered sugar on top.