Preheat oven to 350º. Spray bundt pan with no stick and lightly dust with flour.
In large mixing bowl, combine cake mix, pudding, eggs, sour cream, water and oil. Blend with mixer on low for 1 min: scrape bowl and then blend on medium speed for 2 - 3 mins more. The batter should look thick and well combined.
Fold in the chocolate chips, making sure they are well distributed throughout the batter. Pour into the prepared bundt pan and place in the center of the oven.
Bake until cake springs back when lightly pressed and just starts to pull away from side of pan: about 45-50 mins. Let cool completely and loosen from pan sides with knife and invert it onto a serving dish.
Great when topped with chocolate glaze:
1 stick butter
4 Tbsp unsweetened cocoa powder
1/3 cup milk
4 cups powdered sugar
Melt butter in med saucepan over low heat. Stir in cocoa powder and milk. Let mixture just come to a boil, stirring, and then remove from the heat. Stir in the powdered sugar until thickened and smooth. Pour warm frosting over the cooled cake.