Beat together cake mix, oil, eggs, and milk with an electric hand mixer for a few minutes until batter is smooth.
Spray slow cooker with nonstick spray so the cake won't stick. Pour mixture into the slow cooker and smooth over the bottom.
In another bowl mix the pudding mix and milk until combined. Let thicken for a few minutes. Then pour over the top, do not stir. Then sprinkle chocolate chips over top without stirring.
Cover and cook on HIGH for 2 and 1/2 hours without opening the lid during the cooking time. You'll know when it is done when the outsides and top set up like a sponge and the middle will be gooey. Serve with vanilla ice cream. ENJOY!