Heat broiler. Season steak with ½ teaspoon each salt and pepper and place on broiler-proof rimmed baking sheet. Broil to desired doneness, 3 to 4 minutes per side for medium-rare. Transfer to cutting board and let rest at least 5 minutes before slicing.
STEP 2
Meanwhile, in large bowl, whisk together oil, vinegar, and ¼ teaspoon each salt and pepper. Add peaches and toss to combine. Fold in walnuts, cheese, chives, and steak. Then fold in cress. Serve topped with additional chives if desired.