Neiman Marcus Cake: The Infamous Gooey Million Dollar Bar

Instructions:

1. Preheat oven to 175°C (350°F). Line the 9x13 inch baking pan with parchment paper, leaving an overhang on the long sides (this acts as a sling later). Lightly grease the exposed parts of the pan.
2. Make the Base Dough: In a large bowl, combine the dry cake mix, 115g melted butter, and 1 egg. Mix until a stiff, sticky dough forms.
3. Press the Base: Press the dough evenly into the bottom of the prepared 9x13 inch pan to form an even layer. Set aside.
4. Cream Cheese & Butter: Using an electric mixer, beat the softened cream cheese and the remaining 115g cooled melted butter together until completely smooth and lump-free (about 2 minutes).
5. Add Sugar: Gradually beat in the sifted confectioners’ sugar until fully incorporated and the mixture is fluffy.
6. Add Wet Ingredients: Beat in the 2 eggs, vanilla extract, and salt. Continue mixing until the batter is absolutely smooth and homogenous (this is crucial for the gooey texture).
7. Fold in Chocolate: Gently fold in the semisweet chocolate chips with a spatula.
8. Assemble: Pour the gooey filling evenly over the cake-mix base layer.
9. Bake: Bake for 45 to 50 minutes. The edges should be set, but the center must still have a noticeable, soft jiggle when gently shaken (Do not overbake!).
10. Cool: Remove the pan from the oven and place it on a wire rack to cool completely to room temperature (1–2 hours).
11. Chill (Mandatory): Once cool, transfer the pan to the refrigerator and chill for a minimum of 1 hour, or until firm enough to cut cleanly.
12. Serve: Use the parchment paper sling to lift the entire 'Neiman Marcus Cake' bar out of the pan. Dust liberally with confectioners' sugar before slicing into 16 squares.