Pat dry the steaks and season both sides with salt and pepper. If desired, rub with the cut side of the garlic.
Grill or broil the steaks, turning them once just past the halfway point in the cooking time. Thicker steaks may require broiling farther from the heat or moving the steaks to a cooler section of the grill to complete the cooking. Let rest 5 minutes before serving.
For the chimmichurri:
Whisk the olive oil and red wine vineager together in a small bowl. Stir in the remaining ingredients.
Cover and let stand for 2 hours to allow the flavors to develop. The sauce will keep, covered and refrigerated, for up to 2 days. Serve over meat.