Preheat your oven to 350°F (175°C). Grease the baking pan with cooking spray or butter.
In a large mixing bowl, combine the chocolate cake mix and instant vanilla pudding mix. Whisk until well combined.
To the dry mixture, add the sour cream, Kahlua, vegetable oil, and eggs. Beat with an electric mixer on medium speed until smooth.
Gently fold in the chocolate chips using a rubber spatula.
Pour the batter into the prepared baking pan and spread it evenly.
Bake for 30-35 minutes, or until a toothpick comes out clean.
Allow the cake to cool in the pan for about 10 minutes, then transfer to a cooling rack.
