Ingredients:

  • 280g (2 ¼ cups) All-Purpose Flour (plus extra for dusting)
  • 5g (1 tsp) Fine Sea Salt
  • 170g (6 oz or 1 ½ sticks) Unsalted Butter, cut into ½-inch cubes and deeply chilled
  • 80–100ml (⅓ to ½ cup) Ice Water
  • 1 Tbsp Olive Oil or Neutral Cooking Oil
  • 30g (2 Tbsp) Unsalted Butter (for filling)
  • 1 small White Onion, finely diced
  • 1 medium Leek (white and light green parts only), washed and thinly sliced
  • 60g (½ cup) Carrot, finely diced
  • 30g (¼ cup) All-Purpose Flour (for the roux)
  • 240ml (1 cup) Whole Milk, warm
  • 120ml (½ cup) Chicken Stock (low sodium)
  • 340g (12 oz) Cooked Chicken Breast or Thighs, finely diced
  • 10g (2 tsp) Fresh Tarragon, finely chopped
  • 5g (1 tsp) Fresh Thyme Leaves
  • Salt and freshly cracked Black Pepper, to taste
  • 1 large Egg Yolk
  • 5ml (1 tsp) Whole Milk or Water (for glaze)
  • Pinch of Flaky Sea Salt (for finishing)

Instructions:

  1. Part I: The Pastry - Combine Dry Ingredients: Whisk flour and salt together in a large bowl (or pulse in a food processor).
  2. Cut in the Butter: Add the chilled butter cubes. Work quickly, rubbing the butter into the flour until the mixture resembles coarse breadcrumbs with some pea-sized pieces remaining.
  3. Add Liquid: Gradually drizzle in the ice water, mixing just until the dough comes together. Do not overwork.
  4. Chill: Form the dough into two flat discs, wrap tightly in cling film, and refrigerate for a minimum of 30 minutes.
  5. Part II: The Filling - Sauté Aromatics: Heat oil and butter in a saucepan over medium heat. Add onion, leek, and carrot. Cook gently until softened (about 8–10 minutes). Season lightly.
  6. Create the Roux: Sprinkle the flour over the vegetables and stir continuously for 1 minute to cook out the raw flour taste.
  7. Build the Sauce: Slowly whisk in the warm milk and then the stock. Bring the mixture to a simmer, stirring constantly, until the sauce thickens significantly—it should coat the back of a spoon.
  8. Finish the Filling: Remove from heat. Stir in the diced cooked chicken, tarragon, and thyme. Taste and adjust seasoning (it should be slightly aggressive, as the pastry is unsalted).
  9. Crucial Cooling Step: Transfer the filling to a shallow bowl and refrigerate for at least 30 minutes until fully cooled. Warm filling will destroy the pastry.
  10. Part III: Assembly and Baking - Preheat and Prepare: Preheat oven to 200°C (400°F). Line two baking sheets with parchment paper. Whisk the egg yolk and milk for the glaze.
  11. Roll and Cut: On a lightly floured surface, roll out one chilled dough disc to about ⅛-inch (3 mm) thickness. Use the heart cutter to stamp out an even number of shapes (you should get about 16–20 hearts in total from both discs).
  12. Fill: Place half the heart shapes (the 'bottoms') on the prepared baking sheets. Place 1–2 tablespoons of the chilled filling in the centre of each, leaving a half-inch border.
  13. Seal: Brush the edges of the pastry bottoms with the egg glaze. Top with the remaining heart shapes (the 'lids'). Gently press the edges to seal.
  14. Crimp and Vent: Use the tines of a fork to crimp the edges securely all the way around. Cut two small slits in the top of each pie to allow steam to escape.
  15. Glaze and Bake: Brush the tops generously with the egg glaze, then sprinkle lightly with flaky sea salt. Bake for 28–30 minutes, rotating trays halfway through, until the pastry is deep golden brown and beautifully flaky.
  16. Serve: Allow the pies to cool slightly on the baking sheet for 5 minutes before transferring them to a wire rack.