1.Preheat the oven to 350°F.
2.Mix the cake mix, oats, butter, and 1 egg. Reserve 2 cups of the mixture.
3.Press the remaining mixture into the bottom of a 9x13-inch cake pan.
4.Blend the icing, cream cheese, sour cream, and remaining 2 eggs and pour over the top.
5.Sprinkle the remaining 2 cups of crumb mix over the top and bake for 45-55 minutes.
6.Cool bars to room temperature and then store in the refrigerator.
*Optional: sprinkle with powdered sugar before serving, if desired.