Prepare the Crust: Preheat oven to 350°F (175°C). In a bowl, mix together the cake mix, melted butter, and egg until combined. Press evenly into a greased 9×13-inch baking pan.
Make the Topping: In a separate bowl, combine powdered sugar, cream cheese, and egg until smooth. Spread evenly over the prepared crust.
Bake: Bake in the preheated oven for 35–40 minutes, or until the edges are lightly golden and the center is set.
Cool and Serve: Allow the bars to cool completely before cutting into squares.
