Serve with barbecued peppers and a mayonnaise mixed with chilli and tarragon.
For the marinade:
Method
If the steaks are thickly cut, put each steak between two sheets of cling film and flatten with a rolling pin to about ½" thick.
Place all the marinade ingredients in a blender and blitz until smooth.
Put the steaks in a dish and pour over the marinade. Cover with cling film, put in the fridge and leave to marinate for about 2 hours, turning occasionally.
Drain the meat from the marinade, season on each side and place on a hot barbecue. Cook on each side turning regularly to ensure even cooking.
Baste occasionally with the remaining marinade to keep moist.