Dough. Step 1. Whisk 3½ cups (438 g) all-purpose flour, 2 Tbsp. granulated sugar, and 1½ tsp. Diamond Crystal or 1 tsp. Morton kosher salt in a large bowl to combine. Add 1½ cups (3 sticks) chilled unsalted butter, cut into pieces, and toss with your fingers to evenly coat. Working quickly and aggressively, smash and rub butter into dry ingredients to create large, shaggy pieces (you want some pieces that are flat and thin and some that are large and irregular).. Step 2. Stir ¼ cup chilled vodka (if using), 2 Tbsp. apple cider vinegar, and ¼ cup ice water (or ½ cup ice water if not using vodka) in a small bowl. Drizzle over butter mixture, then mix with a fork until shaggy pieces form. Knead in bowl with your hands a couple of times until a shaggy dough forms (it will look quite dry). Transfer large clumps of dough to a surface. Drizzle 1 Tbsp. ice water over remaining dough in bowl and knead again just to bring it together. Add to dough on surface.. Step 3. Divide dough in half. Working with 1 half, press into a single mass, incorporating dry bits, then pat down to make a ¾”-thick block. Using a bench scraper or knife, divide into 4 pieces. Stack pieces, tucking any unincorporated dry bits in between layers, and press down to flatten and combine. Pat into a ¾”-thick disk and wrap tightly in plastic. Using your fingers and the outside edges of your palms, press in any rough spots or remaining dry bits of dough. Repeat process with remaining dough. Chill disks at least 2 hours (but preferably go at least 12 hours).. Do Ahead: Dough can be made 5 days ahead. Keep chilled, or freeze up to 1 month.. Filling and Assembly. Step 4. Preheat oven to 425°. Let dough sit at room temperature 5 minutes to soften. Working one at a time, roll out disks on a surface lightly dusted with all-purpose flour to ⅛” thick. Place each on a parchment-lined rimmed baking sheet and chill while you prepare the filling.. Step 5. Scrape seeds from 1 vanilla bean, split lengthwise, into a large bowl (or add 1 tsp. vanilla extract); reserve pod for another use. Add 1¼ lb. rhubarb, cut into ½” pieces, 1 lb. strawberries, hulled, halved, quartered if large, ½ cup (100 g) granulated sugar, ⅓ cup (packed; 67 g) light brown sugar, ¼ cup plus 1 Tbsp. cornstarch, 1 tsp. finely grated lemon zest, and a pinch of kosher salt; toss to coat.. Step 6. Carefully transfer 1 dough round to pie dish (using a deep pie dish is critical here). Lift up edges and allow dough to slump down into dish (if it’s too cold to be pliable, let it warm up slightly first). Gently press dough into edges of dish if needed. Trim, leaving about a 1″ overhang. Gently scrape in filling and smooth top. Lay remaining dough round over filling and trim, leaving about a ½” overhang. Fold edge of bottom round up and over top crust; press together to seal and crimp as desired.. Step 7. Beat 1 large egg with 1 tsp. water in a small bowl and lightly brush over crust. Sprinkle with 1 Tbsp. raw or granulate
