Peach-Blueberry Pie

Pulse all-purpose flour, whole-wheat flour, 3 teaspoons sugar and 1/4 teaspoon salt in a food processor until combined, 3 to 4 pulses. Add butter and oil; pulse until the mixture resembles coarse meal, 8 to 10 pulses. Add 4 tablespoons ice water; pulse, adding up to 2 tablespoons more ice water as needed, 1 tablespoon at a time, until the dough begins to clump together. Turn the dough out onto a lightly floured work surface, and shape into 2 (6-inch) disks. Wrap in plastic wrap; refrigerate for at least 1 hour.

Preheat oven to 425 degrees F. Whisk cornstarch, cinnamon, 1/2 cup sugar and the remaining 1/4 teaspoon salt in a large bowl until combined. Add peaches, blueberries and vanilla; stir until evenly coated.

Unwrap 1 dough disk on a lightly floured surface; roll out into a 12-inch circle and fit into a 9-inch pie plate. Spoon the fruit filling into the prepared crust. Unwrap the remaining dough disk; roll out into a 12-inch circle and place over the filling. Fold the dough edges under, seal and crimp. Cut 4 or 5 slits on top of pie for steam to escape.

Brush egg white-water mixture over the top of the pie (you may have some left over). Sprinkle evenly with the remaining 1 teaspoon sugar. Place the pie on a rimmed baking sheet lined with parchment paper.

Bake for 30 minutes, shielding the edges of the crust with foil after 20 minutes. Reduce oven temperature to 375 degrees F; continue baking until golden and bubbly, 30 to 35 minutes. Transfer the pie to a wire rack; let cool for 2 hours before serving.