I just baked a cake for a funeral potluck - pulled it out and my heart sank as I saw the center - a perfect sink hole. I debated filling it in with frosting but it was even too deep for that, and I thought the center might by a horribly thick or gummy texture. As it cooled it sank even further, so I ended up making something else to take instead.

Anyone know why this happens, and how to avoid it in the future? I followed the recipe and my oven's calibrated fine. What's the science here that I'm missing?