You sound like a very experienced baker and it doesn't seem to be tied to oven temp issues or mixing issues - so I just have to think it was a certain Lot of Hines cakes that had something wrong with it. Since you used 2 of the same mixes and it happened both times, the only thing I can think of is the lot...almost sounds like they forgot the rising agent and/or a binding agent.
__________________ ~ A friend told me I was delusional. I nearly fell off my unicorn. ~
°¨¨¨°ºOº°¨¨¨° Ann | Pfeiffer | Marcel Verdel Purcell | Wylie | Artie °¨¨¨°ºOº°¨¨¨° |