Preheat oven to 375 degrees
Line baking sheet with parchment paper
Place puff pastry onto baking sheet
In a bowl, stir together apples, chopped pecans, melted butter, lemon juice, brown sugar and cinnamon
Place filling in centre of puff pastry
Fold borders overlapping each other to partially cover filling
Brush with beaten egg and sprinkle with 1 tsp of granulated sugar
Bake for 25-30 minutes