Mix cake mix, pudding mix, and sugar together. Add water, oil, eggs, and sour cream, blend together with an electric mixer. Fold in chocolate chips.
Bake in a greased and floured bundt pan for 55-60 minutes, or until cake is set.
Cool 10 minutes on a wire cooling rack and remove from pan, and cool another 30-45 minutes.
Melt frosting in a microwave safe bowl until completely melted, stirring every 20-30 seconds. The frosting should be a syrup consistency, if it's watery allow it to cool down.
Place parchment paper or wax paper under cooling rack then pour on frosting. Let cool 60 seconds then decorate with sprinkles.