Perhaps one of the simplest and most satisfying things I've learned to prepare, gratin dauphinoise really makes me appreciate milk and potatoes. This version is only thinly sliced potatoes layered with equal parts whole milk and heavy cream, seasoned with salt, pepper, and ground nutmeg, and baked at 275 for roughly two hours. I've seen other versions (Elizabeth David's comes to mind) that involve rubbing the dish with garlic prior to layering the potatoes. I don't really know that this is necessary, and honestly I've never felt the need to try it.
I should also note that the potatoes I used for this were SunLite "all natural, low carb" potatoes. Now, now, I didn't buy them; they were a gift of sorts. Texturally, they were similar to a Yukon Gold, but not quite that waxy or buttery. Perhaps the most notable quality was how eerily clean they were. Definitely an image-conscious tuber in all respects. A decent potato though--I'll leave it at that for now.