Put the flour and yeast in the mixer bowl. Using the paddle attachment, mix on low, while slowly pouring in the water. Increase speed to medium and mix for 20 minutes-really! You will see it change from a sloppy batter into a surprising shiny, coherent but wet mass, clinging to the paddle. When it is cleaning the sides of the pan this way, add the salt and sugar, and mix a couple of minutes more, to combine it thoroughly. Detach it from the paddle if necessary. Cover and let rise about 4 hours, until it becomes quite light.

This will make a whole half sheet pan of pizza. Or, you can make a combination of smaller pans. Oil your pans very generously with olive oil. Also oil your hands. Spread the dough into a very thin layer in the pan, from the middle, as far as you can without ripping it. When you think you cant get it to go any further, let it rest for 10 minutes, and have another go. Voila! It will stretch a bit more. It can take as many as three or four approaches to get it all the way to the edges. Persist.

Once the dough is covering the pan, cover the whole thing loosely (try not to let the covering touch the dough, it will stick) and let it proof for an hour, until it has begun to be a little puffy. Meanwhile, preheat your oven to 425F, and prepare the topping. Slice the potatoes very thinly, with a mandoline if you have one. Lay them on a big clean kitchen towel, and sprinkle them with salt. Let them sit for 10 minutes, exuding liquid. Then twist the towel up and wring out as much liquid as you can, over the sink. Open the towel, turn them into a fresh towel, and pat them dry. Toss them with the onions and the fresh rosemary to taste.

Spread the topping over the pizza. Brush or spray with olive oil, and sprinkle with more sea salt. Bake about 40 minutes, until the potatoes are nice and crusty and soft enough to pierce with a knife. You can cut this stuff with scissors if you like. I love it.

By the way, I cheat a tiny bit sometimes, using a large flat round pizza pan, which has slightly less surface area than the half sheet. When I do this I try to compensate by making a pinched edge, so it wont lose the ultra thin wonderfulness. At any point in the proceedings, if bubbles appear, try to puncture as few as possible. They are a highly desirable feature, if you are lucky enough to have some make it to the finished product. I adore this pizza.

Whoever created this pizza dough was not only inventive, but also very persistent, for it is quite ornery. If no one had told me that it would work, Id have given up on it, myself. Yet if you keep on, it always comes out right in the end. It makes a wonderful chewy/crispy crust, a marvelous combo with the creamy/crispy potatoes- very greed inducing stuff. And it is perfectly delicious made in an ordinary home stove-though no doubt it would be even better in a woodfired oven. It is a standby of mine. It can, of course, be a supper by itself, with a salad. But I have also served it to friends as a side dish at dinner, cut into rectangles that you can pick up and munch. Please note that the ingredients are so cheap as to be practically free.

In addition to persisting with the dough, it is very important to oil the pan thoroughly, and to dry the potatoes well in a kitchen towel. Failure to do either can result in extreme, irreparable stickiness. (Being more usually a cook than a baker, I always have to remind myself, when baking, that I cannot simply follow my taste and instincts changing things, and expect them to work, as in ordinary cooking. This is not to say, obviously , that I never vary baked things . It seems best, though, to make a recipe as is at first when baking, so I can see what it is supposed to be like, and how it works.) By the way, this recipe needs a stand mixer, for sure.