- 2 1/4 cups all purpose flour
- 1 cup cake flour
- 1 1/2 teaspoons grated lemon peel
- 1/2 teaspoon salt
- 1/4 teaspoon baking powder
- 14 tablespoons (1 3/4 sticks) chilled unsalted butter, cut into 1/2-inch cubes
- 6 tablespoons (about) ice water
- 1 tablespoon apple cider vinegar
- Nonstick vegetable oil spray
- 3/4 cup sugar
- 1/4 cup cornstarch
- 3 cups fresh raspberries
- 3 cups fresh blackberries
- Additional sugar (optional)
- Combine first 5 ingredients in processor; blend 5 seconds. Add butter and blend, using on/off turns, until mixture resembles coarse meal. Add 5 tablespoons water and vinegar. Using on/off turns, blend until moist clumps form, adding more water if dough is dry. Gather dough into ball; divide in half. Shape each half into disk. Wrap in plastic and chill at least 1 hour and up to 1 day.
- Preheat oven to 400°F. Spray 9-inch-diameter glass baking dish with nonstick spray. Whisk 3/4 cup sugar and cornstarch in large bowl to blend. Add berries and toss to coat. Let stand 10 minutes, tossing occasionally.
- Roll out 1 dough disk on lightly floured surface to 12-inch round; transfer to prepared pie dish. Spoon filling into dough-lined dish. Roll out second dough disk to 13-inch round. Drape dough over filling, and trim overhang to 1/2 inch. Press edges together to seal; fold overhang under and crimp decoratively. Cut several small slashes in top crust to vent. Sprinkle with additional sugar, if desired.
- Bake until crust is golden and filling is bubbling, about 50 minutes; cool 30 minutes. Serve warm or at room temperature.