Preheat oven to 400 degrees (maybe my oven is just too hot, but 400 was burning mine so just keep an eye on them, next time I will probably do them either rat 350 or 375). Lightly grease muffin pan (this makes about 20 muffins) or use muffin liners. Set aside. In a mixing bowl combine cake mix and pudding mix. In a separate bowl combine yogurt, water, oil, and eggs. Stir the wet ingredients into the dry ingredients just until combined. Stir in chocolate chips. Fill muffin tins about 3/4 full. Bake 20 -22 minutes or until center springs back. Cool on wire rack. These muffins will store for a couple of days, if you can avoid eating them that long.