Ingredients

For pastry crust:
1 1/2 cups all-purpose flour
1/2 teaspoon salt
3 tablespoons cold unsalted butter, cut into small pieces
1/2 cup mascarpone cheese
1 1/2 tablespoons lemon juice
3 tablespoons ice water
For mushroom filling:
4 tablespoons olive oil
2 ounces diced pancetta
2 shallots, minced
1 pound assorted mushrooms, such as cremini, shiitake, and button
1 tablespoon chopped fresh thyme
1/2 teaspoon salt
1/4 teaspoon freshly ground pepper
1/3 cup (1 ounce) grated smoked mozzarella cheese
1/3 cup ( 1 ounce) grated fontina cheese
2 tablespoons freshly grated Parmesan cheese
1 large egg, lightly beaten

Directions

1. For the crust: In a food processor combine the flour and salt, and pulse to combine. Add the butter and pulse until the butter is finely chopped and the mixture resembles coarse meal. Add the mascarpone and lemon juice and pulse a few times. Add the ice water and run the machine just until the mixture is moist and crumbly, but do not form a ball.



2. Turn the dough out onto a sheet of plastic wrap and press into a disk. Wrap the dough tightly and refrigerate for 20 minutes.
3. For the mushroom filling: Heat 2 tablespoons of the olive oil in a large saute pan over medium-high heat. Add the pancetta and cook until crisp and golden, about four minutes. Using a slotted spoon, transfer the cooked pancetta to a small bowl.
4. Add the remaining 2 tablespoons of olive oil to the pan. Add the shallots and cook for 30 seconds. Add the mushrooms and cook, stirring frequently, until all of the moisture has evaporated, about 12 minutes.
5. Remove the pan from the heat and stir in the cooked pancetta along with fresh thyme, salt, and pepper. Set aside to cool for 10 minutes.



6. Place an oven rack in the lower third of the oven and preheat the oven to 400°F.
7. Unwrap the chilled dough and place it on a sheet of parchment paper. Roll the dough into an 11-inch circle, about 1/4 inch thick. Lift the parchment paper and transfer it and the dough to the baking sheet.
8. Stir the mozzarella and fontina into the cooled mushroom filling and spread in the center of the dough circle, leaving a 2-inch border.



9. Sprinkle the filling with Parmesan.
10. Fold the dough border up over the filling to form an 8-inch round, pleating the edge of the pastry. Brush the crust with beaten egg. Bake the crostata until the crust is golden about 25 minutes. Slice and serve.

Serves 4.