Ingredients:

  • 1 ½ cups (180g) All-Purpose Flour
  • 8 tablespoons (113g) Unsalted Butter (very cold, cubed)
  • 3–4 tablespoons (45–60ml) Ice Water
  • ½ teaspoon (3g) Fine Sea Salt
  • 3 large Yellow Onions (thinly sliced, about 750g)
  • 2 tablespoons (28g) Unsalted Butter
  • 1 tablespoon (15ml) Olive Oil
  • 1 tablespoon (15g) Brown Sugar (packed, optional)
  • 1 teaspoon (5ml) Balsamic Vinegar
  • 2 medium Granny Smith Apples (peeled, cored, and thinly sliced)
  • 1 teaspoon Fresh Thyme Leaves
  • Salt and Freshly Ground Black Pepper, to taste
  • 1 large Egg (lightly beaten with 1 tsp water, for egg wash)
  • ¼ cup (25g) Finely Grated Parmesan Cheese (optional)

Instructions:

  1. Prepare the Pastry: Pulse flour and salt in a food processor. Add cold butter cubes and pulse until mixture resembles coarse breadcrumbs. Slowly drizzle in ice water, pulsing until dough just starts to come together. Form into a disc, wrap, and chill for at least 30 minutes.
  2. Caramelize the Onions: Melt butter and oil in a heavy skillet over medium heat. Add sliced onions and salt. Reduce heat to low-medium and cook slowly for 30–40 minutes, stirring every 5–7 minutes, until onions are deeply golden brown and jammy. Stir in brown sugar (if using) and balsamic vinegar; cook 2 more minutes. Remove from heat and stir in thyme. Set aside to cool slightly.
  3. Roll & Line: Preheat oven to 375°F (190°C). Roll out chilled pastry thinly. Cut circles to fit 6 individual 4-inch tart tins. Gently press dough into tins and trim edges. Prick bases all over with a fork.
  4. Blind Bake Shells: Place lined tins in the freezer for 15 minutes. Line pastry shells with parchment paper and baking weights. Bake for 15 minutes. Remove weights/paper and bake for another 5 minutes until bases look dry.
  5. Assemble and Bake: Divide the cooled caramelized onions evenly among the pre-baked shells. Arrange thinly sliced apples decoratively over the onions. Season apples lightly with salt and pepper.
  6. Finish: Brush pastry edges with egg wash. Sprinkle grated Parmesan over the apples, if using. Bake for 20–25 minutes, or until the pastry is golden brown and apples are tender. Let cool in tins for 10 minutes before transferring to a wire rack.