Position a rack in the middle of the oven and preheat to 200°C (400°F). Line a large baking sheet with parchment paper or a silicone baking mat.
Begin by peeling the apples. Using the large holes of a box grater, grate the apples directly into a medium bowl. This technique ensures quick and even cooking while maintaining moisture in the filling.
Immediately toss the grated apples with granulated sugar, cinnamon, and nutmeg. The sugar will help draw out excess moisture while the spices infuse throughout the mixture.
Assembling the Pastries
On a lightly floured surface, roll out the puff pastry into a large rectangle approximately 3mm (⅛ inch) thick. Ensure the surface is well-floured to prevent sticking.
Using a sharp knife or pizza cutter, divide the pastry into three equal strips lengthwise.
Drain any excess liquid from the apple mixture before using. This prevents the pastry from becoming soggy during baking.
Distribute the spiced apple mixture evenly across each strip of pastry, leaving a 1cm (½ inch) border around all edges.
Working with one strip at a time, fold the long edges into the center, overlapping slightly, like folding a letter. Press gently to seal.
Cut each folded strip into 2-3 equal pieces, creating individual squares or rectangles.
Final Touches and Baking
