1. Heat BBQ according to package directions and keep warm.
2. Preheat oven to 400º F.
3. Line two baking sheets with foil and set aside.
4. Working with one pastry sheet at a time, roll it out on a lightly floured work surface to an 8 x 12-inch rectangle.
5. Cut the pastry into 4, 4 x 6-inch rectangles.
6. Repeat with the second pastry sheet.
7. Place about 1/3 cup BBQ mixture onto ½ of each square and top each with cheese.
8. Working with one rectangle at a time, brush the edges with water and fold the pastry over the filling.
9. Crimp the edges with a fork to seal and place on a baking sheet.
10. Repeat with the remaining rectangles.
11. Brush the tops of each pastry with the egg wash and bake until golden brown (about 20 minutes). Serve warm.