Thai Beef Salad

Serves 4

1 lb. flank steak
salt and ground pepper
3 Tbsp Vegetable oil
1/4 c fresh lime juice
1/4 c fish sauce
4 teaspoons brown sugar
1 sm cucumber peeled and sliced thin
1/2 red onion, sliced thin
1 Tbsp minced fresh cilantro
1 Tbsp minced fresh mint
1 head live butter lettuce, leaves seperated
peanuts (optional)

Pat steak dry with paper towels and season with salt and pepper to taste. Heat 1 Tablespoon of oil in 12 in skillet over med-high heat until just smoking. Brown steak on first side, about 5 min, reducing heat if pan begins to scorch. Flip steak over and continue to cook to desired doneness, 3 to 6 min. Transfer to a carving board, tent with foil and let rest, 5 to 10 minutes.
Whisk lime juice, fish sauce, and brown sugar together until sugar is dissolved. Slice steak in half lengthwise; then slice steak halves thinly widthwise, against the grain. on bias. Toss sliced steak with half lime marinade and set aside for 5 minutes.
Whisk remaining lime marinade with remaining 2 Tbsp of oil, and toss with cucumber, onion, cilantro, and mint. Divide lettuce leaves among individual plates and spoon vegetables with dressing over top. Remove steak from marinade (discard marinade) and lay over salads. Sprinkle with peanuts before serving.