Spray a 9×13 casserole dish with nonstick spray and preheat your oven to 350°F.
Sprinkle the chocolate cake mix evenly in the dish.
Sprinkle the instant chocolate pudding mix evenly across the cake mix.
Add the milk to the butter – make sure the butter isn’t hot, so the milk doesn’t curdle.
Pour the milk/butter mix on top of the cake and pudding mix.
Use a whisk to mix slightly – you don’t need to stir entirely, but you do want it slightly incorporated so that it bakes evenly.
Sprinkle the entire bag of chocolate chips across the top.
Place in the oven to bake for 40 to 45 minutes.
Serve warm with ice cream.
