Mix together the garlic puree or paste, coriander, cumin, chilli and lemon juice and combine well. Season to taste.
Thread the prawns onto 8 skewers and brush with the garlic mixture. Cover and marinate in the refrigerator for 2 hours.
Cook on a barbecue, or place under a preheated grill and cook for 5 minutes each side until the outsides are browned. Serve immediately.