Anne Bryn has a Tunnel of Fudge cake recipe using cake mix and pudding in her Chocolate Cake Doctor cookbook. I would be happy to post it if anyone is interested but she admits that it is not quite as fudgy a center as the original and that, in fact, it firms up as it cools. It, too, has lots of walnuts in it which she says can be cut back on, if desired. I am not sure if you could cut them out completely but cake mixes are usually more adaptable than scratch and not as prone to "disasters". Let me know...