In this recipe by the famed piemakers at Four and Twenty Blackbirds, you'll make a delightfully buttery crust by hand before baking up a juicy peach pie in a cast-iron skillet. Plus: Learn a unique pinwheel crust design. (You can use it on other pies, too!)
Use a bench scraper to cut butter into ½-inch cubes. (If butter begins to "sweat," dust with flour.) In a large, flat-bottomed bowl, combine flour, sugar, and salt. Add the butter cubes and toss to coat with the flour mixture. Use a pastry blender to cut the butter into the flour; do not smash or smear the butter. Scrape butter off the pastry blender during the mixing process and continue mixing. (If butter is softening too fast, put the bowl in the refrigerator until butter firms up, 2–5 minutes.) Continue cutting, working quickly, until butter is broken down and looks like a coarse crumble with only a few larger pieces.
Combine vinegar with water and ice; you’ll use 10–12 tablespoons of this liquid in the pie dough. Begin by sprinkling 4 tablespoons of liquid over the flour mixture; use a bench scraper or your hands to incorporate until the mixture begins to come together. Sprinkle in 4 more tablespoons of liquid and continue the mixing process. Squeeze a fistful of dough: if it holds, like wet sand, it’s ready. If it falls apart, add 1–2 more tablespoons of liquid at a time, squeezing the dough to check if it holds. Bring all the dough together, sprinkling dry bits with more small drops of liquid as necessary; dough will look shaggy. Knead in the bowl just until incorporated.
Turn dough onto a work surface and use a bench scraper to divide dough into two equal pieces. Shape into flat disks and wrap in plastic; refrigerate for at least 30 minutes, preferably overnight. Dough can be refrigerated for up to 3 days and frozen up to 1 month, tightly wrapped.
Crust: Generously grease a cast-iron skillet with butter. Dust a work surface and a rolling pin with flour. Place one of the chilled dough disks on the work surface and roll it out, starting at the center and lightly pressing down with the rolling pin to flatten slightly. Continue rolling, rotating the dough a quarter turn at a time, until it’s an evenly flat circle, about ⅛- to ¼-inch thick and 2–3 inches wider than the skillet all the way around, allowing an extra inch or two if the skillet is deep. (If dough softens too fast, chill in the refrigerator until firm, 2–5 minutes.) Use a pizza wheel to trim the rough edges of the dough circle. Transfer dough to skillet by folding in half and positioning the seam in the center. Unfold the dough, gently center, and fit it into the skillet, leaving no gaps. (Try not to stretch the dough.) Chill in the refrigerator while rolling out the top crust and assembling filling, 30 minutes.
Prepare a decorative pinwheel top crust: Roll the second disk of chilled dough as in Step 1, but ¼-inch thicker than the bottom crust. Place on a sheet of parchment paper. Use a pizza wheel to cut dough into 4 quarters; then cut each quarter into thirds, leaving you with 12 wedges. (They don't have to be exactly the same size.) Transfer to a baking sheet and chill in the refrigerator while preparing filling, 20 minutes.
Filling: Bring a pot of water to a simmer. Prepare an ice bath in a large bowl. Score an “X” into the bottom of each peach and place into the simmering water, 30–60 seconds. Remove peaches and immediately place into the ice water. When peaches have cooled slightly, remove from ice water and peel with your hands, using a paring knife to remove any remaining skin. Cut peeled peaches into ½-inch slices and place in a large bowl.
In another bowl, mix together brown sugar, potato starch, cinnamon, ginger, cloves and salt. Add bitters and mix again. Add lemon juice to peaches and toss to coat; then add peaches to the spice mixture. Mix thoroughly to coat the peaches.
Spoon peach filling into chilled pie crust, including some juices, until the filling is level with the top of the skillet. (If there is extra filling, save for a smaller pie or freeze for future use.) Arrange top crust wedges in an overlapping pinwheel pattern on top of the filling, tucking the last wedge under the first. Use your finger to poke a hole in the center to tuck in the crust points.
Preheat oven to 425 degrees F. Use scissors to trim the top crust wedges to the edge of the skillet. Roll and tuck any excess bottom crust dough inward around the top crust. Crimp the edge of the pie all the way around, making sure the final fluted crust sits directly on top of the skillet’s rim. (Remove some of the dough as you crimp whenever the edge seems too thick.) Refrigerate for 10 minutes.
Brush egg wash evenly over the top of the chilled pie, being careful not to spread any peach juices across the crust. (They will burn during baking.) Sprinkle with raw sugar and place on a rimmed baking sheet. Pie will bake for a total of 1 hour. Bake on the lowest rack of the oven until crust is set and beginning to brown, 20 minutes.
Lower heat to 375 degrees F, move pie to the center oven rack, and continue to bake until crust is a deep golden brown and juices are bubbling throughout, about 35–45 minutes longer. Allow pie to cool completely on a wire rack before cutting into it, 2–3 hours. Serve slightly warm or at room temperature.