Make the Dough: In a large bowl, whisk together the flour and salt. Add the cold, cubed butter and use your fingers or a pastry cutter to work it into the flour until it resembles coarse crumbs. In a separate bowl, whisk the egg, ice water, and vinegar, then pour into the flour-butter mix and stir gently. Knead until the dough forms, wrap in plastic, and refrigerate for at least 30 minutes.,Cook the Filling: Heat olive oil in a large skillet over medium heat. Add the diced onion and bell pepper, cooking until soft (4–5 minutes). Stir in garlic, cumin, paprika, chili powder, oregano, and salt, and cook for another minute. Add shredded chicken and chicken broth, simmering for 5–7 minutes. Stir in green olives and cilantro, then remove from heat to cool.,Assemble the Empanadas: Preheat oven to 375°F (190°C) and line a baking sheet with parchment paper. Roll the chilled dough on a floured surface to 1/8-inch thickness. Cut 4–6 inch rounds. Spoon 2 tablespoons of chicken filling onto one half of each circle, fold, and press edges with a fork to seal.,Bake: Brush the empanadas with egg wash and bake for 20–25 minutes until golden brown and crispy.