"Old-Fashioned" Cherry & Blueberry Galette

Name: "Old-Fashioned" Cherry & Blueberry Galette
Cook time: 3 h
Total time: 3 h
Cuisine: European, Mediterranean, French
Ingredients: 0.75 cup all-purpose flour, plus more for dusting; 0.75 cup whole-wheat pastry flour; 0.25 teaspoon salt; 5 tablespoons cold unsalted butter, cut into 1/2-inch pieces; 3 tablespoons canola oil, cold; 5 tablespoons ice water; 2 cups fresh cherries, pitted and halved; 2 cups blueberries; 0.5 cup granulated sugar; 4 tablespoons cornstarch; 3 tablespoons bourbon; 1 tablespoon lemon juice; 1 tablespoon orange zest; 1 teaspoon vanilla extract; 0.125 teaspoon salt; 3 teaspoons 2% milk, divided; 1 tablespoon turbinado sugar