Ok, tried to do a half dh yellow and dh devils food cake in a 11 x 15 pan. The baking times were off by 2-3 minutes on box, so I thought I would be ok, but when I cooked them the yellow baked fine but not the chocolate. Still not cooked through in center. Used two flower nails evenly spaced in middle of pan. Temp set for 325 and baked for 46minutes. The recipe I used was a doctored Wilton recipe (dream whip). Any suggestions. I would even do the dh yellow cake made into chocolate if possible using this recipe so they would bake the same. I did try just adding cocoa powder to a dh yellow cake mix,but it tasted terrible on my trial cake. Saw on an older forum. Any help is greatly appreciated as I am new to this.
The recipe that is used is:
dh mix
envelope dream whip
4 eggs
cup milk








