Instructions

• Preheat the oven to 350°F. Lightly grease a 13-by-9-inch baking pan and set it aside.
• Make the crust: In a medium bowl, combine 1 box devil's food cake mix, 1 egg, and 8 Tbsp melted butter. Beat with an electric mixer on medium until combined and evenly moistened.
• Press the cake-mix mixture firmly and evenly into the bottom of the prepared 13-by-9-inch pan.
• Make the filling: In a large bowl, beat 1 (8-oz) package softened cream cheese until smooth. Add 1 cup Nutella and beat until combined and smooth.
• Add 3 eggs, 1 tsp vanilla, and the remaining 8 Tbsp melted butter to the cream cheese–Nutella mixture. Beat until blended.
• Add the entire 1 (16-oz) box powdered sugar and mix on low to medium speed until the filling is smooth and fully incorporated, scraping down the sides of the bowl as needed.
• Spread the Nutella–cream cheese filling evenly over the pressed cake-mix crust.
• Bake in the preheated 350°F oven for 40 to 50 minutes, until the edges are set and the center remains slightly gooey. Do not overbake.
• Remove the pan from the oven and let the cake cool on a wire rack. Allow it to cool until it is set enough to slice (cooling completely will make slicing cleaner). Slice and serve.