Put the prawns into a large bowl and add the oil, lemon juice, garlic, ginger, chilli powder, honey and salt. Mix well and marinate for about 10 minutes.
Remove the prawns from the marinade and thread 2 prawns alternately between 2 pieces of mango on each of 8 presoaked wooden skewers.
Place the skewers under a preheated hot grill, brush with the remaining marinade and grill for 2 minutes on each side or until the prawns turn pink and are cooked through. Serve 2 skewers per person with some dressed mixed leaf salad, if liked.