In a large bowl, stir cake and pudding mixes together. Add 4 beaten eggs, oil, water, milk and yogurt, mixing well. Stir in chocolate chips by hand. Spray a ...large... crock pot with vegetable non-stick spray. Cook on low for 2 - 2 1/2 hours. DO NOT OPEN THE LID WHILE COOKING. Serve with vanilla ice cream.
NOTE: Crock pots are not created equal! Some crock pots cook faster than others. A good suggestion is to check on the cake after it has cooked for two hours, then determine if it needs to cook longer. Cake is done when middle of cake looks set.