Preheat oven to 350 °F. Spray or grease a 9x13" pan. Melt butter in the microwave and then combine with the cake mix and egg. Add chopped pecans. Pour into prepared 9x13" pan and set aside.
In a large bowl, beat the cream cheese and the confectioners' sugar until well combined. Add in eggs one at a time and beat until combined.
Pour cream cheese mixture over crust. Bake for 45 minutes or until a toothpick or cake tester comes out clean. Cool, then slice and serve.
Notes
Store these in a closed container in the fridge, but they are best eaten the day of as the cake hardens.
You can freeze these in a closed container for up to 3 months.