Preheat oven to 400 degrees F. Line a baking sheet with parchment paper or nonstick cooking spray; set aside.
In a mixing bowl or stand mixer, combine self rising flour and Greek yogurt until a thick dough forms. Roll dough out onto a lightly floured surface into a large rectangle (approximately 10”x14”).
Spread 1⁄2 cup BBQ sauce onto the dough, leaving a 2-inch border around the perimeter. Sprinkle 1 1⁄2 cups mozzarella on top of the sauce. In a small bowl, combine cooked chicken and remaining 1⁄2 cup BBQ sauce then spread on top of cheese and sprinkle red onion on top.
Roll the dough up (like you would cinnamon rolls), pinch the edges together, tucking under, then place seam side down on the prepared baking sheet. Brush the top of the dough with egg wash and sprinkle on remaining cheese. Gently cut diagonal slits in the top of the dough every two inches.
Bake for 22-25 minutes or until golden brown and heated through. Let rest for a few minutes, then cut into slices and garnish with cilantro before serving.