01 -
Preheat your oven to 350°F (175°C). Grease a 9×13 inch baking dish with cooking spray or butter.
02 -
In a large mixing bowl, combine the chocolate cake mix and creamy peanut butter. Use a fork or pastry cutter to mix until a crumbly texture forms.
03 -
Add the milk, vegetable oil, eggs, and vanilla extract to the crumb mixture. Mix with an electric mixer on medium speed for about 2 minutes until you have a smooth, consistent batter.
04 -
Gently fold in the chocolate chips and chopped peanut butter cups using a rubber spatula. This adds extra texture and delicious pockets of flavor throughout the cake.
05 -
Pour the batter into your prepared baking dish, using the spatula to spread it evenly and smooth the surface for uniform baking.
06 -
Bake in the preheated oven for approximately 35 minutes, or until a toothpick inserted into the center comes out with a few moist crumbs (not wet batter).
07 -
Allow the cake to cool completely in the pan on a wire rack, about 1 hour. Once cooled, dust the top with powdered sugar if desired, for a sweet, elegant finishing touch.
08 -
Cut into squares and serve. For an extra indulgent treat, serve warm with a scoop of vanilla ice cream.