. Difficulty: Hard
. Serves: 6 people
. Preparation time: 2 hours and 15 minutes
. Variety: Savoury pie
IngredientsFor the dough:
2 cups all-purpose flour, plus more for rolling out the dough
1 teaspoon kosher salt
½ cup extra-virgin olive oil
⅓ cup cold water, plus more as needed
For the filling:
1 pound small zucchini
½ cup Italian short-grain rice, such as Arborio, Carnaroli, or Vialone Nano
2 cups ricotta, preferably fresh, drained overnight
1 cup freshly grated Grana Padano
2 bunches scallions, trimmed and finely chopped (about 2 cups)
3 large eggs, lightly beaten
2 cups milk
2 teaspoons kosher salt
Unsalted butter, for the baking pan
PreparationFor the dough:
Pour the flour and salt into a food processor fitted with the metal blade. Pulse a few seconds to aerate the dough. Mix the oil and water together and, with the processor running, pour the liquid through the feed tube and mix for about 30 seconds, until a soft dough forms and gathers on the blade. If the dough is too dry, add water in small amounts until you have a smooth, very soft dough.
Turn the dough out onto a lightly floured surface, and knead by hand for a minute. Pat into a rectangle, and wrap loosely in plastic wrap. Let rest at room temperature for 30 minutes.
For the filling:
Shred the zucchini on the coarse holes of a box grater into a large bowl. Toss the rice and shredded zucchini together, and let sit for 30 minutes to an hour, until the grains have absorbed the vegetable liquid. Fold in the ricotta (breaking up any lumps), then the grated cheese, scallions, beaten eggs, milk, and salt, stirring thoroughly until mixed.
Preheat the oven to 375 degrees. Spread the butter on the bottom and sides of a 12-by-18-inch rimmed sheet pan.
On a lightly floured surface, roll the dough to a rectangle at least 4 inches longer and wider than the baking sheet. Transfer the dough to the pan, either by folding it in quarters and lifting it onto the sheet, or by rolling it up around the floured rolling pin and then unfurling it over the baking sheet. When the dough is centered over the pan, gently press its center flat against the bottom, and rim the pan, leaving even flaps of overhanging dough on all sides. (If the dough tears as you are moving it, patch it with a bit of dough from the edges.)
Scrape the filling into the dough-lined pan, and spread it to fill the crust in an even layer. Fold the dough flaps over the top of the filling, pleating the corners, to form a top-crust border that looks like a picture frame, with the filling exposed in the middle.
Set the pan in the oven, and bake until the crust is deep golden brown and the filling is set, 45 minutes to an hour. About halfway through the baking time, turn the pan in the oven, back to front, for even color and cooking. Cool the crostata on a wire rack for at least 30 minutes to set the filling before slicing. The crostata can be served warm or at room temperature, cut into pieces in any shape you like.