Preheat oven to 400 degrees.
Line a baking sheet with parchment paper.
In a small bowl, mix together the room temperature butter, brown sugar, cinnamon and vanilla.
Take the thawed pastry dough sheet and cut into 6 equal rectangles.
Transfer to the baking sheet and spread a couple teaspoons of the mixture onto each rectangle.
Place the apple slices with the skin side up onto each pastry rectangle. Fold the edges upwards, pinching to seal the corners.
Drizzle any remaining sugar mixture onto the apple slices.
Brush edges of pastry with the melted butter.
Bake in the oven 25-30 minutes, or until the
edges are golden brown. Serve warm!