1/2 cup cake flour?

This is a bit late, but I had the same question recently and found this helpful: http://www.pastryaffair.com/blog/2012/1/10/tuesday-tip-how-to-make-cake-flour.html

I would think more flour is the answer

Ok, here's an update. I ended up baking them for about 15 minutes. They are puffier than the photos, and probably not as wet. Still delicious.

I can't edit the question, so I'll post the details here. I'm making these now. I refrigerated the dough. After 10 minutes they are kind of a soft (delicious chocolate) mess. I'm thinking there is not enough flour relative to the amount of fat in this recipe. I baked off the first dozen (put a melted glob in vanilla ice cream-- delicious-- but not what I was going for,) and have a bowl of dough in the fridge. I'm thinking of adding more flour and baking powder. What do you think? Thanks.