Preheat oven to 300 degrees. Spray a 13 x 9 pan with cooking spray.

Mix cake mix, melted butter and one egg in a bowl. Press into the bottom of the pan.

In a mixer, mix remaining 2 eggs, cream cheese and powered sugar. Beat until smooth, about 1 - 2 minutes. Pour over crust.

Bake for 40 - 50 minutes until the top is golden brown.

Remove from oven and cool. Refrigerate for a few hours until cold. Cut into squares and serve.