Someone else here did it first, and I liked what I saw, so tried it out.
Just sliced up some potatoes, (the more evenly the better), and laid them in a greased skillet, wedged some onion pieces in between some of them (the space helps cooking), threw in a few dollops of butter, some roughly minced raw garlic, salt, pepper, rosemary, and a few tablespoons of water. closed the lid and let it go for a couple of hours. Halfway through, I sprayed some cooking oil on them to help them crisp up. Cherry wood smoke for the first bit.
Actually leftover is just as good, or better. Serve with some sour cream and chives - OMFG, really good.