Chimichurri Flank Steak Salad

Season the flank steak with salt and pepper and let it sit at room temperature 20 minutes. 2. Make the chimichurri: finely chop the parsley, cilantro, and garlic, then stir together with the red wine vinegar, olive oil, oregano, red pepper flakes, and a pinch of salt. Let it stand while you cook. 3. Heat the grill or a grill pan to high. Grill the steak 4-5 minutes per side for medium-rare, until an instant-read thermometer reads 130F. 4. Rest the steak 10 minutes on a cutting board, then slice thin against the grain. 5. Toss the arugula, cherry tomatoes, and red onion with a spoonful of the chimichurri and divide among plates. 6. Lay the sliced steak over the greens and spoon the remaining chimichurri on top.