Everybody loves pizza, but sometimes it is intimidating and seems difficult to make at home. This is a version of baked dough, but as its base it has potatoes and it is not leavened, so it’s easier to handle and yet has all the flavors and feel of pizza. There are endless ways of making and baking dough in the Italian tradition, not to mention in all the different cultures of the world, but there is something basic and sacred about the simplicity of turning grains into bread. It is a direct link between the earth and sustenance for human beings. We need to reflect and understand and get to know the earth, and the food it provides. Children, especially today, are far removed from the basic source of food, so bring your children into the kitchen with you and let them feel the dough in their hands. Let them wonder how this magic can happen from the earth we stomp on.
1 pound russet potatoes
1½ cups all-purpose flour, , plus more for rolling the dough
2 teaspoons baking powder
2½ teaspoons kosher salt
1 large egg, beaten
2 tablespoons -extra--virgin olive oil , plus more for cookie sheet
12 ounces fresh mozzarella, thinly sliced
4 cherry or other small tomatoes, thinly sliced
1 teaspoon dried oregano
¼ cup grated Grana Padano or Parmigiano Reggiano
Preheat the oven to 350 degrees F. Put the whole, unpeeled potatoes in a pot with water to cover by a couple of inches, and bring to a simmer. Cook the potatoes until they are easily pierced with a knife but not falling apart, about 20 minutes. Let them cool slightly, then peel, press through a ricer onto a sheet pan, and let cool completely.
Scrape the potatoes into a bowl, and sift over them the flour, baking powder, and salt. Mix in the egg to make a smooth dough. Oil a -15--by--10--inch cookie sheet with olive oil. On a floured surface, roll the dough out to a rectangle almost as large as the cookie sheet, or as large as you can get it. (If the dough is difficult to roll, roll between layers of parchment paper.) Transfer to the cookie sheet, and press the dough out to almost reach the edges of the pan.
Top the dough evenly with the mozzarella, leaving a -½--inch border around the edges. Top with the sliced tomatoes, then drizzle with the 2 tablespoons olive oil. Sprinkle with the dried oregano and grated cheese. Bake until the crust is browned on the bottom and cooked through, about 35 minutes. Allow the pizza to cool on the baking sheet for a few minutes before cutting into squares to serve.