Apple Slab Pie

Instructions

1. Prepare the dough
   In a large bowl, whisk together flour and salt. Add the cold cubed butter and use a pastry cutter or your fingers to work it into the flour until pea-sized crumbs form. Gradually add ice water, stirring with a fork until the dough begins to come together. Divide dough into two portions (one slightly larger than the other), form into rectangles, wrap in plastic, and refrigerate for at least 1 hour.
2. Make the filling
   In a large bowl, combine the sliced apples, granulated sugar, lemon juice, cinnamon, nutmeg, allspice, and cornstarch. Toss gently until apples are evenly coated. Let the mixture sit for 15 minutes to allow the flavors to meld and juices to release.
3. Assemble the pie
   Preheat oven to 375°F (190°C). Roll out the larger portion of dough on a floured surface into a rectangle approximately 12×17 inches. Transfer to a 10×15-inch rimmed baking sheet, allowing the excess to hang over the edges. Spread the apple filling evenly over the dough.
4. Add the top crust
   Roll out the remaining dough into a rectangle slightly larger than 10×15 inches. Place it over the filling. Fold the edges of the bottom crust up and over the top crust, pinching to seal. Cut several slits in the top to allow steam to escape. Brush the top with egg wash and sprinkle with coarse sugar.
5. Bake the pie
   Bake in the preheated oven for 45-50 minutes, until the crust is golden brown and the filling is bubbling through the slits. If the edges brown too quickly, cover them with aluminum foil.
6. Cool and serve
   Allow the pie to cool on a wire rack for at least 1 hour before cutting into squares. This helps the filling set properly. Serve warm or at room temperature, optionally with vanilla ice cream or whipped cream.