1/2cupCreamy Peanut Butter(for the ganache; smooth)
1/2cupHeavy Cream
Instructions
Preheat your oven to 350°F (175°C). Grease a 9×9-inch baking dish (or a 9×13-inch for thinner slices) with butter or nonstick spray. Line with parchment if you like easier removal.
In a medium bowl, combine the German chocolate cake mix, 1 large egg, and 1 stick (113 g) of melted butter. Stir until well combined; the mixture will be thick and slightly crumbly.
Press the chocolate mixture evenly into the bottom of the prepared pan using the back of a spoon or your fingertips to form a compact base.
In a clean mixing bowl, beat the softened cream cheese until smooth using a hand mixer or stand mixer on low speed.
Add the remaining 2 large eggs and 1 cup creamy peanut butter to the cream cheese. Mix until fully combined and smooth.
Gradually add the 2 cups confectioners’ sugar, beating between additions until the filling is silky and lump-free.
Add the remaining stick (113 g) of melted butter and 1 teaspoon vanilla extract. Mix until the filling is creamy and spreadable.
Pour the peanut butter cream cheese mixture evenly over the pressed cake base, smoothing the top with a spatula.
Bake for about 50 minutes, or until the edges are set and the center is slightly jiggly — do not overbake, as you want that gooey texture.
Remove from oven and let the cake cool partially on a wire rack while you prepare the ganache.
Place 3/4 cup semi-sweet chocolate chips, 1/4 cup peanut butter chips, and 1/2 cup creamy peanut butter into a heatproof bowl.
Heat 1/2 cup heavy cream in a small saucepan over medium heat until it just begins to simmer (small bubbles around the edge). Immediately pour the hot cream over the chips and peanut butter.
Let sit undisturbed for 1–2 minutes, then stir gently until the mixture becomes smooth and glossy.
Pour the ganache evenly over the warm cake, spreading it to the edges.
Let the cake sit at room temperature for about 1 hour, or until the ganache sets slightly. Slice into squares and serve warm or at room temperature.
Notes
Store leftovers covered in an airtight container for up to 4 days in the refrigerator. For freezing, wrap individual squares tightly in plastic wrap and place in a freezer-safe container for up to 3 months.