Blend green chaat chutney: Blend cilantro, green chilies, lemon juice, salt, thin sev, and ice cubes until smooth and bright green. Adjust salt and spice to taste. Set aside.
Prepare base: Combine roasted murmura, farsan mix, masala peanuts, and chaat masala in large bowl.
Add vegetables: Add crushed papdi, chopped onion, tomato, raw mango, and boiled potatoes. Mix gently.
Add chutneys: Add green chutney, tamarind chutney, and lime juice. Mix until evenly coated.
Final mix: Add half the sev and chopped cilantro. Mix quickly and taste for seasoning.
Serve: Transfer to bowls, top with remaining sev, chana dal, cilantro, and crushed papdi. Serve immediately.