Place the steaks in a single layer in a shallow dish. Combine the remaining ingredients, except the salt, in a small bowl. Pour over the steaks and turn to coat. Cover and marinate in the fridge for 4 hours, turning occasionally.
Preheat your barbecue to medium-high. Lightly oil the grill if prone to sticking. Season the steaks with salt and grill to the desired doneness, allowing 2 minutes per side for rare, 3 minutes for medium rare, and 4 minutes for medium.