Ingredients:

  • 2 1/2 cups All-Purpose Flour
  • 1 Tablespoon Granulated Sugar (for crust)
  • 1 teaspoon Fine Sea Salt (for crust)
  • 1 cup Unsalted Butter, very cold, cut into 1/2-inch cubes
  • 1/2 cup Ice Water
  • 3 cups Fresh Blueberries
  • 3 cups Fresh Blackberries
  • 3/4 cup Granulated Sugar (for filling)
  • 1/4 cup Cornflour (Cornstarch)
  • 1 teaspoon Lemon Zest
  • 1 Tablespoon Fresh Lemon Juice
  • 1/4 teaspoon Salt (for filling)
  • 1/2 teaspoon Vanilla Extract
  • 1 Large Egg, beaten (for egg wash)
  • 1 teaspoon Milk or Water (for egg wash)
  • 1 Tablespoon Turbinado (Coarse) Sugar (for sprinkling)

Instructions:

  1. Whisk together flour, sugar, and salt in a large bowl.
  2. Add the cold butter cubes. Use a pastry blender or pulse in a food processor until the mixture resembles coarse meal with some pea-sized pieces of butter remaining.
  3. Drizzle in ice water, one tablespoon at a time, until the dough just comes together when pinched. Do not overmix. Divide the dough into two disks, wrap tightly in cling film, and chill for at least 60 minutes.
  4. Gently toss blueberries and blackberries in a large bowl. In a separate small bowl, whisk together the filling sugar, cornflour (cornstarch), lemon zest, lemon juice, salt, and vanilla extract. Pour the dry mixture over the berries and gently fold until the fruit is evenly coated. Set aside.
  5. Preheat oven to 425°F (220°C). Place a baking sheet on the middle rack while the oven heats up to ensure the bottom crust receives immediate high heat.
  6. Roll the larger dough disk into a 12-inch circle. Carefully transfer the dough to the 9-inch deep dish pie plate. Trim the edges, leaving about 1 inch of overhang. Spoon the berry mixture into the pastry shell.
  7. Roll out the remaining dough disk to create a full top crust (vented with slits) or a lattice pattern. Place the top crust over the filling. Trim the edges, fold the top and bottom dough together, and crimp firmly to seal.
  8. Brush the entire top surface with the egg wash (beaten egg mixed with milk/water) and sprinkle generously with Turbinado sugar. Bake on the preheated baking sheet at 425°F (220°C) for 15 minutes.
  9. Reduce the oven temperature to 375°F (190°C). Continue baking for 45–55 minutes, or until the crust is golden brown and the filling is bubbling thickly. If edges brown too quickly, shield them with foil. Remove from the oven and allow the pie to cool on a wire rack for a minimum of 3 hours before slicing.