# What You'll Need:
→ Pastry
01 - 2 sheets puff pastry, thawed (approximately 17.6 oz)
02 - 1 large egg (for egg wash)
03 - 1 tablespoon whole milk
→ Apple Filling
04 - 3 medium golden apples, peeled, cored, and diced
05 - 2 tablespoons unsalted butter
06 - 1/4 cup granulated sugar
07 - 2 tablespoons brown sugar
08 - 1 teaspoon ground cinnamon
09 - 1/4 teaspoon ground nutmeg
10 - 1/2 teaspoon pure vanilla extract
11 - 1 tablespoon fresh lemon juice
12 - 1 tablespoon cornstarch
→ Optional Topping
13 - 2 tablespoons coarse sugar, for sprinkling
# Steps:
01 - Set oven temperature to 400°F. Line a baking sheet with parchment paper.
02 - Melt butter in a skillet over medium heat. Incorporate diced apples, granulated sugar, brown sugar, cinnamon, nutmeg, and lemon juice. Sauté for 4 to 5 minutes until apples soften.
03 - Add vanilla extract and cornstarch to the apple mixture. Continue cooking for 1 to 2 minutes until thickened. Remove from heat and allow to cool slightly.
04 - On a lightly floured surface, roll out puff pastry sheets if needed. Divide each sheet into 4 equal squares, yielding 8 squares total.
05 - Place a generous spoonful of apple filling onto the center of each pastry square. Fold each square diagonally to form a triangle and firmly press to seal edges. Crimp edges using a fork.
06 - Arrange turnovers on the prepared baking sheet. Whisk egg with milk and brush the mixture over the turnovers. Sprinkle with coarse sugar if desired.
07 - Make a small slit on top of each turnover with a sharp knife to allow steam to escape. Bake for 20 to 25 minutes until golden brown and puffed.
08 - Transfer turnovers to a wire rack and cool for 10 minutes before serving.