Mix prawns with spices, mustard oil, ginger-garlic paste, let rest for 10 minutes (PW1, PW2).

Heat 1½ butter packs, grill prawns for 2-3 minutes on each side (PW5).

Light the coal, arrange prawns around it (PW3).

Pour remaining butter over the coal, cover for 1-2 minutes to infuse smoky flavor.

Serve hot with green chutney (PW4).