Those have always been my favorites and I suddenly was curious as to whether this was something I could make at home.
Since I trust ATK/Cook's Illustrated, I began there. Followed their recipe and technique. But it didn't work out as I expected, so on to more research.
Well, it turns out that:
1) OMG the reason they are so good is that they are essentially made up of FAT and
2) I don't think it's possible to make them correctly without the dough-dropping device that they use commercially.
The dough itself is/can be the same as the basic cake donut, but it's the frying process that creates the unique shape/form:
Normally, donuts are fried at around 350 degrees, but these "old fashioneds" are fried at 300 which is pretty low for frying. What happens is that the dough pretty much oozes from the interior out and forms that characteristic craggy crust. I think that the dough has to be pretty wet to start out with, which is why it's difficult to make at home since you cannot really pick up the formed donut to transport it to the oil. I think that's why those dropping devices are critical.
But actually, it's good that they're difficult to make at home, because when you realize how much fat (Crisco is the best to use) they soak up at that low temp... omg, it's frightening. I made some at the higher temp and the lower temp and the weight difference between them was shocking.