Prepare the Dough:In a large mixing bowl, combine flour, baking powder, baking soda, sugar, and salt.Add yogurt and oil, mix, then knead with warm water until soft and pliable.Knead 8–10 minutes until smooth, cover, and let rest 1–2 hours.Prepare the Filling (Optional):Boil and mash 2 medium potatoes.Sauté cumin seeds, green chilies, garam masala, coriander powder, and salt in 1 tsp oil; mix with potatoes.Optionally add coriander leaves or other fillings like paneer or garlic-herb butter.Shape the Kulchas:Divide dough into 8–10 portions.Flatten each portion, add filling if using, and seal.Roll gently into circular or oval shapes, 5–6 inches in diameter.Cook the Kulchas:Heat a skillet or tawa on medium heat.Cook each kulcha 1–2 minutes per side until bubbles form; optionally finish on an open flame.Brush with melted butter or ghee.Serve:Serve hot with curry, chole, or yogurt. Optionally sprinkle chili powder or garlic flakes.