Trim the fat from the pork and cut the pork into 25 mm (1 in) cubes (24 pieces in all). Core and seed the peppers, then cut into 24 squares, 25 mm/1 in in size.

Put the pork cubes and finely chopped onion in a bowl with salt and freshly ground black pepper and 90 - 120 ml (6 - 8 tbsp) olive oil. Add the green pepper squares. Toss well, cover the bowl with a plate and refrigerate overnight. Remove from the refrigerator 1 - 2 hours before cooking to allow the meat to come to room temperature.

When ready to cook, remove the meat and green peppers from the onion mixture and arrange alternately on 4 skewers. Brush with the olive oil and onion mixture. Season the brochettes with salt and freshly ground black pepper. Place on a grill/broiler over hot coals and cook for about 20 minutes or until tender, turning the skewers frequently and basting several times during cooking. Serve immediately.