1. Place your shredded meat in a bowl and pour in the barbecue sauce. Mix well and let sit for about 20 minutes.
2. Sauté your onions in olive oil for about 20 minutes until they have wilted and started to caramelize. Add the peppers and mushrooms and sauté for a few minutes more.
3. Roll out your puff pastry into a large rectangle.
4. Add the shredded meat into the center from end to end. Top the meat with the onions and peppers.
5. Roll into a tight log with closed ends.
6. Brush the top with egg. Garnish with sesame seeds. Place onto a baking sheet lined with Gefen Parchment Paper and bake for 40 minutes.