Cinnamon Swirl Apple Slab Pie
- 3 tablespoons all purpose flour plus more for dusting
- 2 recipes Pate Brisee (butter based crust)
- 4 tablespoons unsalted butter, room temp, plus 2 tablespoons cold cut into small cubes
- 1/2 cup packed light brown sugar
- 1 teaspoon cinnamon
- 1/2 teaspoon kosher salt
- 4 pounds assorted apples (granny smith, jonagold, rome) peeled, cored, cut into 1/4" slices
- 2 tablespoons fresh lemon juice
- 6 tablespoons sugar
- 1 teaspoon vanilla
- 1 egg, slightly beaten
- Sugar or cinnamon sugar for sprinkling
On a lightly floured piece of parchment roll one disk of dough into a 12 x 17 rectangle. Transfer the crust to a 10 x 15 inch jelly roll pan and press into bottom edges and up sides. Fold overhang under and around edge. Refrigerate 30 minutes.
In a small bowl, combine room temperature butter, brown sugar, cinnamon and 1/4 teaspoon salt. On a lightly floured piece of parchment roll second disk of dough into a 12 x 16 rectangle. Evenly spread butter mixture over dough all the way to the ends then start rolling at a long edge tightly roll into a log. Transfer to a baking sheet and refrigerate until firm, about 30 minutes.
Preheat oven to 425 with a rack in lower third and a foil lined baking sheet on the rack below. In a large bowl, toss together apples, lemon juice, sugar, flour, remaining 1/4 teaspoon salt and vanilla. Fill piecrust with apple mixture and dot with butter.
Cut dough log into 1/4" slices. You'll need 63 slices. Arrange slices over apple mixture, slightly overlapping in 9 rows of 7. Refrigerate until firm, about 30 minutes.
Brush top of pie with egg wash and sprinkle with sanding sugar or cinnamon sugar. Bake until top crust is just set, 20 minutes. Reduce temperature to 375 and continue baking until crust is golden brown and juices are bubbling, about 1 hour. Let cool completely on a wire rack.