Whisk first ten ingredients in a medium bowl. Using a sharp knife, pierce meat all over. Place in a ziplock bag and add the marinade. Refrigerate at least four hours or overnight. Prepare barbecue for medium-high heat. Remove steak from plastic bag and grill to desired doneness, about 3-4 minutes per side for medium to medium-rare (depending on thickness). Serve immediately with the orzo.
If you cannot find grape tomatoes, use cherry tomatoes.
1/4 cup balsamic vinegarIn a large pot, boil about 3-4 quarts of water for the orzo. Add the orzo and cook until done, about 8 minutes. Drain in a colander and then put into a large mixing bowl. Whisk together the balsamic vinegar and olive oil. Pour over the orzo and mix until coated. Add in the cherry tomatoes, chopped green onions, and oregano, and stir until mixed well. Can be served warm or room temperature.