Apple Butter Slab Pie - flour

Method

• Make the pie dough: in the bowl of a food processor, pulse the flour and salt to combine (if your food processor is small, you'll need to mix in two batches, just divide the mixture in half). Add the cold butter and pulse until the butter is broken into smaller pieces - the largest pieces should resemble walnut halves. Remove the mixture from the food processor and transfer to a medium bowl.
• Make a well in the center of the flour mixture and add the cold water into it. Mix to combine, then continue to add water 1-2 tablespoons at a time until the dough is evenly moistened. It should hold together easily, not be crumbly - it shouldn't be tacky or sticky to the touch. Adding the water by hand makes it easier to reach the ideal consistency.
• Form the dough into a rough rectangle shape about 1 inch thick. Wrap tightly in plastic wrap and refrigerate for at least 30 minutes.
• Make the apple butter: cut each apple in quarters. Place each quarter on it's side and use a knife at a 45 degree angle to cut a diagonal slice from the center of the apple, removing the core. Dice the apples and transfer them to a large pot.
• Add the sugar, cinnamon, cloves, nutmeg, and salt and toss until the mixture is well combined. Add the apple cider, water, and vinegar to the pot. Heat the mixture over medium heat and cook, stirring occasionally, until the apples are very soft and tender, and the mixture has thickened, 1 - 1 1/2 hours. Use a hand blender to puree the mixture until it is relatively smooth, 1-2 minutes. Let the apple butter cool completely (chilled is even better).
• Preheat the oven to 425°F / 218°C, preferably with a baking stone on the bottom rack. Have ready a 13 x 18 inch baking sheet (half sheet pan).
• On a lightly floured surface, roll out the pie dough into a slightly larger rectangle than the baking sheet - about 20 x 15 inches. The dough should be about 1/4 inch thick. Roll up the dough onto the rolling pin, and unfurl onto the baking sheet. Gently press the dough into base and the corners to make sure it's laying flat against the pan - it should come up the sides of the baking sheet. Chill the dough inside the pan for 15-25 minutes.
• Use a paring knife to trim it away by holding it flushly parallel to the edge of the pan and trimming all around. Dock the base all over with a fork. Cover the crust using one large (or a few smaller pieces) of foil. Place another baking sheet on top of the crust and par-bake until the edges appear firm and set, but are only just beginning to lightly brown - 17-20 minutes. Remove the top pan and the foil and return to the oven until the base of the dough appears dry, 2-4 minutes more. Cool completely.
• While the crust cools, make the streusel: in a medium bowl, mix the flour, brown sugar, ground ginger, and salt to combine. Add the butter and mix by hand or with a pastry cutter until the mixture forms large, moist crumbs. Fold in the crystallized ginger.
• To finish the apple butter filling, measure out 5 cups of prepared apple butter, and whisk in the eggs. (NOTE: if you want to use prepared apple butter, you can skip steps (4-5).
• Pour the apple butter filling into an even layer inside the cooled par-baked crust. Sprinkle the streusel evenly over the surface.
• Transfer the pie to the oven and bake until the filling bubbly and the streusel is golden brown, 40-45 minutes. Cool completely before slicing and serving.