To prepare the prawns, butterfly them through the back. To do this, press each prawn flat on a chopping board, back uppermost. Carefully, with a small serrated knife, cut the shell and prawn nearly all the way through. Turn over, open the prawns out and press flat.
Arrange in a tray awaiting their marinade. Sprinkle with the lemon juice, season liberally with salt, then scatter with the chilli and garlic. Finally, add a good amount of olive oil. Marinate for up to 2 hours in the fridge.
To cook the prawns, you have two choices: ridged grill pan or a large frying pan. Place the prawns, very carefully, shell down in or on the hot pan (whatever) in a single layer fairly snugly. They are not moved after this until done and they need no extra oil, only a little of the marinade spooned over them as they cook. It may be necessary to do several batches. If so, transfer directly to your serving plate. They will cook very quickly and are easy to spoil by overcooking.
After 2 or 3 minutes over the heat (which should be quite fierce), the prawns will start to shrivel in their shells and turn pinky white. Juices will collect in the shell. They should continue to cook until only the very centre area remains translucent, bluish and raw. Quickly turn them over and grill on the flesh side for no more than 1 minute.
When all the prawns are cooked and transferred to the serving dish, scatter with the parsley, tomato and onion. A little extra oil may be appropriate, lemon juice certainly is. Leave to cool while the flavours blend. Do not refrigerate.
© 1996 Alastair Little. All rights reserved.