You can add 2 eggs and 1/2 a cup of oil to turn any cake mix into cookie dough.
Adam Rifkin stashed this in Recipes!
Sounds like it works:
I have done this. They were a hit at my office Christmas cookie party.
I used 3 eggs, though, because the batter was too thick with just 2.
Also, sub coconut oil instead of regular oil for extra flavor.
Sometimes, I bring a bowl of dough and a pan to my friends' dinner parties so they can enjoy the baking aroma.