Grate the rind from the limes. Place the rind, chilli, sugar and salt into a small food processor. Process until well combined. Transfer to a bowl.
Half the limes. Juice two lime halves.
Slice the cheeks from each Calypso® mango. Score each portion deeply into the flesh in a cross-hatch pattern, cutting down but not through the skin. Spoon the lime juice over the mangoes, allowing the juice to run between the cuts. Sprinkle 1 tsp chilli lime salt over each.
Preheat a clean barbecue plate or chargrill on high heat. Place a piece baking paper onto the hot barbecue plate. Working quickly, place 4 mango cheeks, cut side down onto the paper. Barbecue for 4-5 minutes until charred. Remove to a board. Repeat with remaining mango, using a fresh sheet of baking paper.
Sprinkle a little more chilli lime salt over each mango half. Serve with fresh prawns, rocket and remaining lime.