I made my Guinness cake last night, and the same question I had a year ago has reared it's ugly head: why does the darn thing volcano out?
I just read through all the different versions I tried, since I thought I had a "Eureka" moment this morning that would solve the problem.
Of course I already attempted what I thought of today, or something close anyway.
There's something just a bit off in the chemistry of that cake. Though the flavor is fantastic, it balloons completely out of control out of the pan and it drives me NUTS!
I think if I was making a regular cake, in a regular pan, there wouldn't be any cracks.
Part of me thinks it's because of double acting baking powder. Here's what double acting baking powder does: it begins leavening when it hits liquid and then the double acting part comes into play when the internal temperature of the cake reaches a trigger point that kicks in further leavening power.
OK...one more experiment with that darn cake. Just baking soda.
Gotta go do some research.