Place the white crabmeat and claw meat into a bowl, add the chopped mango, avocados, red onion, garlic, red chilli, thyme leaves, lime juice and olive oil, then season, to taste, with salt.
Preheat the oven to 150C/130C Fan/Gas2. Extract all the meat from the crab but reserve all the shells. Place the shells with the olive oil in a shallow roasting pan with the carrot, leek and onion.