Instructions

1. Place 1 of the pie doughs on a lightly floured work surface and roll into a 12-inch round about 1/8-inch thick. Transfer the dough into a standard 9-inch pie plate and press into the bottom and up the sides. Refrigerate.
2. Line a rimmed baking sheet with parchment paper. Roll out the remaining pie dough into a 10 to 11-inch round. Cut the round into quarters. Transfer to the baking sheet in a single layer and refrigerate.
3. Prepare the following, adding each to the same large bowl as it is completed: Core and thinly slice 2 1/4 pounds green tomatoes (1/8 to 1/4-inch thick). Finely grate the zest of 1/2 medium lemon until you have 1 teaspoon. Juice the lemon until you have 1 tablespoon.
4. Add 1 cup granulated sugar, 4 teaspoons cornstarch, 1 1/4 teaspoons ground cinnamon, 1/4 teaspoon grated or ground nutmeg, and 1/4 teaspoon kosher salt. Gently toss until well combined. Let the mixture sit for 15 minutes. Meanwhile, arrange a rack in the middle of the oven and heat the oven to 350ºF.
5. Strain the juices in the bowl of tomatoes (about 1 1/3 cups) into a small saucepan and return the tomatoes to the bowl. Bring the juices to a boil over medium heat and cook until thick, viscous, glossy, and reduced to about 3/4 cup, about 8 minutes. Meanwhile, cut 2 tablespoons unsalted butter into 8 pieces. Place 1 large egg in a small bowl and whisk with a fork until well beaten.
6. Remove the saucepan from the heat. Transfer the tomato mixture to the pie plate and arrange into an even layer. Drizzle with the reduced tomato juices. Evenly scatter the butter over the filling.
7. Working with one piece at a time, arrange the 4 dough triangles on top of the filling with the pointed end in the center, barely shingling the next piece on the last, until the entire pie is covered. Roll the excess dough over on itself and crimp with your fingers or a fork to seal the edges. Place the pie on the now-empty baking sheet.
8. Brush the beaten egg all over the surface and edges of the dough. Evenly sprinkle all over with 2 tablespoons raw or demerara sugar. Cut a 1-inch slit in each quadrant of the pie with a paring knife.
9. Bake until the pie is deep golden brown all over and the tomatoes are tender, about 1 1/2 hours. Check after 1 hour: If the crust is getting too dark, tent the pie loosely with aluminum foil and continue baking. Let cool for at least 4 hours for the filling to firm up. Serve with vanilla ice cream or a drizzle of heavy cream if desired.