Plum Galette with Cornmeal Crust

Ingredients

For the crust:

• 1 cup all-purpose flour, plus more for dusting
• ¼ cup fine cornmeal
• 1 tablespoon natural cane sugar
• ½ teaspoon coarse salt
• 1 stick (1/2 cup) cold unsalted butter, cut into small pieces
• 1 large egg yolk
• 2 to 4 tablespoons ice water

For the filling:

• ¼ cup natural cane sugar
• 1 vanilla bean, split and seeds scraped
• 2 tablespoons cornstarch
• 1 ¼ pounds small plums, pitted and sliced into ½-inch wedges
• 1 tablespoon unsalted butter, cut into pieces
• 1 large egg lightly beaten with 1 teaspoon water
• Raw sugar, such as turbinado, for sprinkling

Instructions

1. 1
   Make the Crust: In a food processor, combine flour, cornmeal, cane sugar, and salt. Add butter and pulse just until mixture resembles coarse meal.
2. 2
   In a bowl, lightly beat egg yolk; add 2 tablespoons ice water. With machine running, add egg yolk mixture in a slow, steady stream. Pulse until dough just holds together; add up to 2 tablespoons more water, 1 tablespoon at a time, if necessary. Gather dough into a ball and flatten into a disk. Wrap in plastic. Refrigerate at least 1 hour and up to overnight.
3. 3
   Make the Filling: In a bowl, stir together cane sugar and vanilla seeds; stir in cornstarch. Add plums and toss until coated. On lightly floured parchment, roll out dough to a 12-inch round, ¼ to 1/8 inch thick. Transfer dough and parchment to a baking sheet. Arrange plums in center of dough, leaving a 2-inch border. Fold border over filling, overlapping slightly and pressing to adhere folds. Dot butter over filling. Refrigerate until firm, about 30 minutes.
4. 4
   Preheat oven to 375 degrees. Brush edges of dough with egg wash and sprinkle with raw sugar. Bake, rotating sheet halfway through, until crust is golden brown and juices are bubbling, 45 minutes. Transfer baking sheet to a wire rack and let galette cool. Serve warm or at room temperature. (Galette is best the day it’s made. Dough can be frozen up to 1 month; thaw overnight in refrigerator before using.)