01 -
Preheat oven to 350°F (177°C) and prepare a 9×9-inch or 9×13-inch baking dish, depending on desired cake thickness.
02 -
Combine the cake mix, 1 egg (reserve the other two eggs for filling), and 1 stick (113 g) of melted butter. Mix until well combined. Pat the mixture into the prepared pan and set aside.
03 -
In a stand mixer with a paddle attachment or a hand-held mixer, beat the cream cheese on medium speed until smooth. Add the remaining 2 eggs and peanut butter, mixing until combined.
04 -
Lower the mixer speed and gradually add the confectioners' sugar. Slowly pour in the remaining 113 g (1 stick) of melted butter, followed by the vanilla extract. Mix until completely smooth.
05 -
Pour the filling mixture over the cake layer in the pan. Bake for 50 minutes, ensuring the center remains slightly gooey. Avoid overbaking.
06 -
Let the cake partially cool on a wire rack while preparing the ganache topping.