Preheat oven to temperature indicated on cake mix box for a bundt pan. (approx 350-375 degrees F)
Make cake according to box directions. Add pudding mix powder (do not make pudding) to cake mix. Stir with a wooden spoon until smooth, and repeat with sour cream. Fold in chocolate chips.
Pour into a greased bundt pan. Bake for 45 mins. Cake may rise higher than pan while baking, but will fall slightly when taken out of the hot pan.
****Cake is delicious served warm with a scoop of vanilla ice cream or whipped cream. If refridgerated overnight, you will have a dense, sinfully rich, well-chilled cake with a consistency similar to a cheesecake the next day.