Preheat the oven to 350℉. Grease a 12-cup bundt pan.
In a large mixing bowl, blend together your cake mix with sugar, sour cream and oil on low for about 1-2 minutes.
Add eggs one at a time, beating well between each addition.
Continue to beat for 2-3 minutes on medium speed. Add in vanilla extract and stir well. Mix in the chocolate chips.
Pour batter into your prepared bundt pan and bake for 50-60 minutes or until a skewer or knife inserted in the center comes out clean. Ovens vary so watch cake carefully.
Allow cake to cool for about 15-20 minutes then invert onto a cake plate.