Ingredients:

  • 2 ½ cups All-Purpose Flour
  • 1 tablespoon Granulated Sugar (for crust)
  • 1 teaspoon Fine Sea Salt (for crust)
  • 1 cup (2 sticks) Unsalted Butter, cold and cubed
  • ½ cup Ice Water
  • 3 cups Fresh Blueberries, rinsed and dried
  • 3 cups Fresh Blackberries, rinsed and dried
  • ¾ cup Granulated Sugar (for filling)
  • ¼ cup Tapioca Starch (or cornstarch)
  • 1 tablespoon freshly squeezed Lemon Juice
  • ½ teaspoon Ground Cinnamon or Nutmeg
  • Pinch Fine Sea Salt (for filling)
  • 1 Large Egg (for egg wash)
  • 1 teaspoon Milk or Water (for egg wash)
  • 1 tablespoon Demerara or Turbinado Sugar (for topping)

Instructions:

  1. Combine the All-Purpose Flour, 1 tablespoon sugar, and 1 teaspoon salt in a large bowl or food processor.
  2. Add the cold, cubed butter. Work quickly using a pastry cutter, your fingertips, or pulse the food processor until the mixture resembles coarse, pea-sized crumbs. Ensure a few larger chunks of butter remain.
  3. Gradually drizzle in the ice water (start with 100ml / 6 tbsp), mixing just until the dough barely comes together. Do not overmix; the dough should look shaggy.
  4. Divide the dough into two slightly unequal disks (the larger one for the bottom crust). Flatten each disk, wrap tightly in plastic wrap, and refrigerate for a minimum of 2 hours, or up to 2 days.
  5. Prepare the filling: Ensure the blueberries and blackberries are completely dry. In a separate medium bowl, whisk together the remaining ¾ cup granulated sugar, tapioca starch, cinnamon/nutmeg, and salt. Add the berries and lemon juice, tossing very gently until fully coated.
  6. Preheat the oven to 400°F (200°C). Remove the larger dough disk and roll it out into a 12-inch (30 cm) circle. Carefully transfer the dough to a 9-inch deep-dish pie plate. Trim the edges, leaving a 1-inch overhang, tuck the excess dough underneath, and prick the bottom crust all over with a fork (docking).
  7. Spoon the berry mixture evenly into the prepared crust, mounding slightly in the center. Roll out the second, smaller dough disk for the top crust (or lattice) and place it over the fruit.
  8. Trim the excess top dough, crimp or seal the edges firmly, and cut 4–5 small ventilation slits in the top crust. Whisk the egg with milk/water, brush the entire surface with the egg wash, and sprinkle with Demerara sugar. Place the assembled pie in the fridge for 15 minutes.
  9. Bake at 400°F (200°C) for 15 minutes. Reduce the oven temperature to 375°F (190°C) and continue baking for 50–60 minutes until the crust is deeply golden brown and the filling is visibly bubbling thickly in the center vents.
  10. Remove the pie from the oven. Let the pie cool completely on a wire rack for a minimum of 3–4 hours before slicing to allow the starch to set properly.