I keep reading about these doctored mixes, and I am wondering if I can do that to a DH marble mix. My sister really just wants a vanilla and chocolate cake for her birthday, and I would like to make it as special as possible.
Thanks in advance!

I'm sure you could do this. You'd have to use the doctored cake mix for each the vanilla and the chocolate then swirl in the chocolate after you've poured your vanilla batter into your pan... good luck and let us know how it turns out for you!

Thanks, I will give it a try!