1. Mix all the ingredients if possible 2 or 3 hours before the barbecue so that the marinade soaks up the herbs.
2. Coat the rib with this marinade and leave to rest for 2 hours in the refrigerator.
3. For even more tender meat, take it out 30 minutes before cooking.
4. Sprinkle with truffle, garlic and chili powder then brown the meat on the barbecue.