Preheat oven to 200°C. Mix maida, salt, sugar, baking powder in a bowl, add milk and sufficient water and knead into a soft dough.
Cover with damp cloth an set aside for 30-40 minutes. Mix potatoes, green chillies, pomegranate seeds, salt, red chilli powder, chaat masala and mix well.
Divide dough into equal portions, stuff each with potato mixture and roll into balls. Place each on work top and press with fingers to ensure that the potato mixture spreads evenly.
Further dust with a little dry flour and roll out into slightly thick kulchas. Place them on baking tray lined with silicon sheet and bake for 7-8 minutes or till golden and crisp. Brush with a little butter and serve hot.