In a medium-sized bowl add the cake mix, eggs, and oil. Start blending with a hand mixer for a few seconds before adding the coffee. Slowly add the coffee and finish blending. Do not over blend, some lumps are fine.
In another bowl mix the pudding mix and milk until combined. Let thicken for a few minutes.
Spray the slow cooker with non-stick spray. Add the cake batter. Then add the pudding by dropping dollops over the cake mix. Sprinkle over the chocolate chips.
Cover and cook on HIGH for 3 hours without opening the lid during the cooking time.
Video
Notes
An oval slow cooker works best for this, so the cake portion gets cooked evenly.