Soak 12 bamboo skewers in cold water for 30 minutes. Cut each bacon rasher into 3 pieces crossways, then run the back of a knife along the length of each piece to stretch them out thinly.
Wrap each prawn carefully with bacon and thread on to a soaked bamboo skewer with a tomato and basil leaf. Season each skewer with a little salt and pepper.
Spray the skewers with a little oil and cook on a hot barbecue for 2—3 minutes on each side until the prawns are cooked through. Squeeze with lemon juice and serve hot.