Step 1 – Prep
Preheat oven to 350°F (175°C). Lightly grease a 9x13-inch baking dish or line with parchment paper.
Step 2 – Make the Crust
In a large bowl, mix cake mix, egg, and melted butter until a soft dough forms. Press evenly into the bottom of the baking dish.
Step 3 – Make the Filling
In a separate bowl, beat cream cheese until smooth. Add eggs, vanilla, and melted butter; mix until fully combined. Gradually beat in powdered sugar until light and creamy.
Step 4 – Assemble and Bake
Pour the filling over the crust and spread evenly. Bake for 40–45 minutes. The edges should be golden; the center should still jiggle slightly.
Step 5 – Cool and Serve
Let cake cool completely in the pan. Dust with powdered sugar after cooling. Slice into squares and serve.