Preparation

• Bring a 3-quart saucepan of well-salted water to a boil. Boil the orzo according to package directions. Drain, rinse with cold water, and transfer to a medium bowl.
• Prepare a medium (375°F) gas or charcoal grill fire.
• Put the lamb and halloumi in a large bowl. In a small container with a lid, combine the olive oil, vinegar, oregano, garlic, red pepper flakes, 1 tsp. salt, and 1/2 tsp. pepper. Cover tightly and shake vigorously. Toss the orzo with 1/3 cup of the mixture and pour the rest over the lamb and halloumi, tossing to coat.
• Thread 6 pieces of lamb, 2 pieces of halloumi, and 2 tomatoes onto each of eight 12-inch metal skewers, alternating a tomato and a piece of cheese between every 2 pieces of lamb. Grill, turning once, until the halloumi is browned and the lamb is pink in the center (cut into a piece to check), 4 to 6 minutes total.
• While the lamb is cooking, toss the scallions, mint, lemon juice, 1/2 tsp. salt, and 1/4 tsp. pepper with the orzo. Season to taste with more salt, pepper, and lemon juice. Serve the skewers with the orzo.