1/2 pound of boneless tender beef steak (sirloin or top loin)
4 Tbsp. Kikkoman Stir-fry sauce, divided
1 pound Swiss chard or romaine lettuce
2 Tbsp. oil, divided
1 medium onion, cut into 1/2-inch strips
1/8 to 1/4 tsp. crushed red pepper flakes
1/8 tsp. salt
1/2 cup unsalted roasted peanuts

Cut beef across grain into thin slices. Coat with 1 tablespoon stir-fry sauce; let stand 10 minutes. Separate and rinse chard; pat dry. Cut leaves crosswise into 1-inch strips, separating stems from leaves. Heat 1 tablespoon oil in hot wok or large skillet over high heat. Add beef and stir-fry 1 minute; remove. Heat remaining 1 tablespoon oil in same pan. Add chard stems, onions, and red pepper. Sprinkle with salt and stir-fry 4 minutes. Add chard leaves; stir-fry 2 minutes. Add beef and remaining 3 tablespoons of stir-fry sauce; cook and stir until veggies are coated with sauce. Remove from heat, stir in peanuts.

Serves 2-3