1. In a bowl combine sourdough starter, warm water, olive oil, and salt, then mix in flour until a soft dough forms.

2. Knead dough on a floured surface for 5–7 minutes until smooth, cover, and let rest for 1–2 hours.

3. Preheat grill to medium-high heat (around 400°F).

4. Brush chicken with olive oil and season with smoked paprika, garlic powder, black pepper, and chili powder.

5. Grill chicken 4–5 minutes per side until cooked through and charred, then let rest and slice thinly.

6. In a saucepan combine ketchup, apple cider vinegar, brown sugar, Worcestershire sauce, mustard, and smoked paprika; simmer 10 minutes and cool.

7. Divide dough into four portions and roll each into a 1/4-inch-thick oval.

8. Brush each piece with olive oil and grill 1–2 minutes per side until bubbly and charred.

9. Spread BBQ sauce on grilled flatbread, top with sliced chicken, cheese, and onions, then return to grill until cheese melts.

10. Garnish with fresh cilantro, slice, and serve hot with extra sauce on the side.