The last couple of batches of my chocolate chip cookies went from delicous to foamy tasting although I was using the same recipe and ingredients and sam measuring methods. I'm confused as to why the texture changed so drastically.
Your dough warmed up and the fat started to melt. In between batches, keep the dough cold in the fridge.
Over-mixing the dough will also contribute to cake like cookies if a whole batch comes out like that.