Preheat oven to 400 degrees F. Line a baking sheet with parchment paper or spray with 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 larger rectangle (approximately 10”x14”); place on prepared baking sheet and set aside.
Add ground beef and onion to a large skillet over medium-high heat and cook for 6-8 minutes, breaking up meat, until meat is cooked through and onion is tender. Add black beans and cook until heated through.
Season meat mixture with salt, pepper, cumin, paprika and garlic powder then mix to combine. Add water and cook for a few minutes, stirring occasionally, until water has evaporated; remove from heat.
Spread beef mixture down the center of the dough leaving 2-3 inches of dough on each side. Top with ¾ cup cheese. Use a pizza cutter to cut 1-inch diagonal strips down each side of the dough. Fold 1-inch strip sup and over the filling, alternating sides to create a braid.
Brush egg on the top and sides of the braid and sprinkle remaining ¼ cup cheese on top. Bake for 20-22 minutes, or until golden brown on top. Remove from oven, let rest for a few minutes then cut into slices before serving.